


In Eridu

by takadainmate



Category: Supernatural
Genre: Action/Adventure, Historical, Hurt/Comfort, M/M
Language: English
Status: Completed
Published: 2011-08-08
Updated: 2011-08-08
Packaged: 2017-10-22 10:02:16
Rating: Mature
Warnings: Graphic Depictions Of Violence
Chapters: 1
Words: 66,437
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/236861
Author URL: https://archiveofourown.org/users/takadainmate/pseuds/takadainmate
Summary: <blockquote class="userstuff">
              <p>In Chicago, there are omens that point to something big. There's a heatwave that won't end, and the only clues Dean and Sam have to go on are a long history of people going missing from around Lake Michigan and Castiel's weird behaviour.</p><p>Six thousand years earlier two other brothers fight to save their world from a slow, pitiless end by calling down the creature responsible. What they get is something they'd never expected, and the brothers come to think that maybe this being, who is powerful and righteous and calls itself Castiel, can save them all.</p>
            </blockquote>





	In Eridu

**Author's Note:**

> Written for the J2_spn Big Bang on LJ.
> 
> Thanks to cienna for beta-ing and encouragment, and to weirdwednesday and littlehollyleaf for aplha duties.
> 
> The art for my fic can be found [here](http://users.livejournal.com/__hibiscus/195329.html), created by the talented __hibiscus.

****

1.

Dean hadn't been back to Chicago since Death. Even if that had only a year ago, with all the shit that had happened since then it might as well have been ten.

As he drove into the city, windows wound down as far as they'd go, the stifling heat impossible to avoid, Dean could see the effect the heat wave was having on people. They moved slowly along the sidewalks, sweating and miserable and gathering in the shade. Not that it made much difference. On the roads no one had any patience, and Dean guessed they longed for their homes and the prospect of air conditioning, or water, or at least to be away from the painfully slow crawl of traffic through the city where the heat was at its most intense.

On the radio, the announcer warned of water shortages, of heatstroke, of looting, and Dean had no clue how anyone had the energy for it in this. They'd only arrived a couple of hours ago and already Dean wanted out. He hated cities anyway, but this was fucking insane, and all the forecasts predicted worse to come.

Pressure fronts and freak storms in Alaska and pollution build-up had all been used to explain the long, slow slide into record temperatures. It wasn't even summer yet, barely even spring, and people made excuses and told themselves it'd be over soon, it was nothing, but Dean had seen the signs. He had read the articles Sam had found in the local papers and on the internet that reported on the decimation of fish stocks in Lake Michigan, and of the disappearances. It reeked of the supernatural, even if no one else wanted to believe it. So here they were, stuck in traffic, drinking through the last of their bottle of water- warm now but better than nothing- and wishing they'd bought more at the last gas station.

It wasn't like they were in a hurry or anything, only just coming on to the case, and the lethargy this kind of heat induced made it impossible to move very fast anyway. But they had a lot of groundwork to cover and Dean kind of wanted to get to the lake before sundown. The air was so freakily dry, and everything in his car was burning to the touch, and he wanted this job done as quickly as possible.

With something like this though, Dean knew, there was no way it was going to be anything they could just fix up in a night or two.

Something like this took real power. There'd been a shit load of omens, change in weather patterns, and Bobby had heard rumours of unprecedented numbers of ghosts and ghouls and other nasties crawling about Chicago. While that wasn't exactly anything new these days, it was unusual in such a concentrated area. There was no doubt that something big was going on, and the dry heat- like driving into a freaking oven- only made Dean more certain they were dealing with something bad. He hadn't felt this tense, had such a strong sense of _wrongness_ since the apocalypse.

He'd never say it out loud but it was kind of freaking him out.

In the seat beside him, shifting uncomfortably and sweating all over the upholstery, Sam was wearing his most worried look. His laptop sat open on his knees and that had to be really freaking uncomfortable. As though the heat around them wasn't bad enough. Typing slowly in between rubbing at his eyes and pushing his hair back from his face, whatever Sam was finding could not be anything good, if the sighing and muttering were any indication.

It didn't look like they were going very far anytime soon. Seeking distraction from the noise and the boredom and the discomfort Dean leaned back in his seat, stretched out his arms as he gripped the steering wheel, and asked, "You find anything?"

Sam shrugged and shook his head. "I've found a ton of things, but none of them add up to anything that makes sense."

"This had better not be the end of the world again," Dean griped and grimaced, because way to jinx it. That uneasy feeling was stronger than ever, and Dean had always trusted his instincts. It was probably just the heat, Dean told himself, and the claustrophobia he always felt in big cities.

Sam glanced up at Dean before turning back to his computer screen, typing away at a few keys. "Cas would've told us if it was, wouldn't he?"

Only in the life of the Winchesters was the end of the world not a single event. Worse, Dean hated that his first thought was, _Not if he's dead he wouldn't._

They hadn't heard anything from Cas in days. Not exactly unheard of, or even unusual these days, but yeah, there was that _bad feeling_ Dean couldn't shake. It wasn't that he was worried. The angel was big enough to take care of himself, except maybe not so much against the host of Heaven. They were just human though, and what they hell could they do to help even if Cas did ask for it?

Wiping the stinging sweat, the tiredness, from his eyes, Dean replied, "Who knows?"

Dean thought about praying. If he were honest with himself he thought about praying to Cas a lot more often than he'd like. But Cas had a war to fight and he'd made it very clear that he did not appreciate being disturbed. Nothing had actually happened that could credit calling down an angel. Not yet anyway. Maybe that was the point. Maybe whatever this was caused a hundred little things that nobody noticed instead of one big thing that had everyone screaming and running away, allowing it to sit back, take its pickings, and nobody knew any better.

They've seen shit like this before, and they'd never yet failed to stop it. This time, Dean knew, wouldn't be any different.

***

Back on Lake Shore Drive, however the fuck many miles and a bajillion hours ago, Dean had noticed the smell.

Then, it had been faint, not much more than a hint of rotting fish and carcasses that Dean had thought wasn’t all that weird for a boiling city. As though the heat wasn't bad enough, as they'd gotten closer to the lake the smell had gradually turned into a stench until Dean was breathing through his mouth so he didn't gag and Sam was grimacing and hiding his face in his shirt, pulled up over his nose.

They were both sweaty, grouchy, and aching from hours sitting in more or less gridlocked traffic, and just to make it the perfect day there was this horrific smell. So the first question Dean asked when they'd finally found someone who would talk to them was, "Why the hell have all the fish just been _left_ there."

Not his most diplomatic opening, but Jesus, standing next to a lake blanketed by dead, decaying fish bloated and floating on the surface and smelling it up close and personal was enough to make anyone pissy.

The guy, a grizzled old charter boat captain, frowned at Dean. "They haven't," he said, not looking at all happy.

It was spring, and the marina should have been heaving with tourists, but there was nothing but rotting fish and boat owners hanging around, cleaning fish guts out of their engines and hoping for crazy fish-smell loving visitors to show up. Or something. With the relentless heat it would have been kind of nice, Dean thought, to get out on the lake, take a swim, maybe there was a breeze out there even. It would have been awesome, if not for the dead fish.

"These are just today’s," the captain went on. "It's the same every morning." He gestured towards the lake. "There ain't gonna be any fucking fish left soon."

"Least it'd smell better," Dean murmured, and didn't miss the sour look the captain gave him. Nor did he miss the way Sam elbowed him.

Ignoring Dean's comment, Sam asked, "When did all this start, sir?" He sounded polite and interested, and Dean wondered if soulless Sam could have done that. Would soulless Sam even have noticed the heat? This was normal Sam, though, and even if this Sam looked tired and kept fidgeting and pulling at the front of his t-shirt Dean was glad to have him back.

From the way the captain was eyeing Sam suspiciously, for a moment Dean thought he wasn't going to answer, like he thought they were somehow making fun of him. They really needed this guy though, and sometimes Dean really wished he'd learn to keep his mouth shut. He was going to blame his bad mood on the heat. It didn’t help that everyone they'd spoken to that day had been pissy and unfriendly as hell. If this heat wave didn't break soon, Dean thought, Chicago was going to turn into an ugly place.

"Please. Anything you can tell us would be really helpful." Somehow, despite his obvious discomfort Sam still managed to sound earnest.

"You gonna be able to change this damned weather?" the guy scoffed.

Sam shrugged noncommittally. It was always difficult to know just how much to tell civilians. How much they were willing to believe before they called bullshit, or what was the best lie. Over a lifetime of practice they’d both gotten good at the deception and the leading questions and the best way to keep witnesses talking, but people were always unpredictable.

At last the captain said, "It started three weeks ago. Right before the weather went screwy." He looked away from them, staring out at the lake. What water could be seen around all the fish lay motionless, the boats tethered to the moorings hardly moving at all. "It isn't natural."

Dean had to admit, the lake's surface looked creepy, like someone had hit the pause button.

"We heard there were some boats found with their passengers and crew missing." Sam said. "Is it true?"

More than the freak heat wave and the dead fish, the reports of missing people were what had brought them to Chicago. No signs of struggle. No damage. Just no one left aboard. Unless it was all some weird prank then there was no way these incidents weren’t somehow supernatural.

And damn but these people were distrustful. The captain's eyes narrowed. "What newspaper you say you're from again?"

"The Daily Herald," Sam replied smoothly, lifting his notebook and pen as though it were proof enough.

The guy hummed, but answered, "It's bad for business, so you keep this to yourselves."

"Of course," Sam said, and Dean would have believed him too from the solemn look on his brother’s face.

"I saw them bring in the second boat.” The old guy shook his head. “Not a soul left aboard. No one's found them yet."

"Does anyone know what might have happened?" Sam asked.

"Not a clue." The captain pulled himself upright from where he was leaning, looking off into the distance and avoiding meeting their eyes and Dean was pretty sure he knew something.

"But you've got an idea, right?" Dean encouraged. "Some theory?"

"Not a theory." The guy waved his hand dismissively. "The boats were all found around South Manitou Island. Been a lot of stories about that place for a long time. A lot of shipwrecks there."

Stories. Right. There were always stories and every time they came across this kind of thing- some place knee-deep in local legends and superstition- it was almost impossible to tell what was bullshit and what was true.

Sam somehow managed to look intrigued, like he’d never heard of anything like this before in his life. "Stories?"

"Weird crap like folk seeing monsters and noises at night. There's an old, abandoned lighthouse there. Some people think it’s haunted." The captain snorted derisively. "I think it's dumb college kids."

Sam nodded grimly in a way that Dean guessed was supposed to show he completely agreed. He let the captain bitch for a while about rich kids renting boats when they knew nothing about them and cared even less, getting themselves killed, polluting the lake, being loud, drunken assholes. From the way Sam shifted from foot to foot, looking thoughtful, Dean could tell though that Sam already planning their next move. Dean agreed that this was definitely a lead. It was better than the fuck-all they'd managed to gather from the news reports and the police channels so far anyway.

"Thank you for your help," Sam eventually managed to break in. It was clear they weren't going to get anything more useful out of this guy. It was getting to dark, too, but the sky was cloudless and clear; great weather for hunting. If it weren’t for the heat making his throat dry and his eyes heavy and tired it would've been perfect. Despite it being close to sunset now the temperature didn’t seem to be cooling down any either.

When they were a fair distance away from the boats and the locals out for a walk, probably trying to find relief from the heat, Dean asked, "What d'you think?"

His shirt was soaked with sweat, he could feel it running down his back and down his legs and it was gross. He would've worried how badly they smelled, if it wasn't for the continuous, over-powering odour of rotting fish that filled the air. As far as Dean could tell there was no escaping this heat anywhere, and the exertion of trekking for a couple miles round the lake was starting to burn.

"Could be ghosts," Sam said. "But they couldn't have done all this." He lifted his hands, turned his palms upwards, and Dean had to agree that he'd never seen a spirit even close to being powerful enough to fuck with a whole city's weather. "Demons are more likely."

"Yeah. Or maybe one of those pain-in-the-ass gods." They certainly had the mojo for it, though Dean couldn't see any motive. Unless they were insane, which was way too likely a reason as any for why supernatural beings did anything.

"Or angels," Sam suggested, and Dean shrugged, conceding the point, because that was possible too. What Dean saw as a random mix of omens might have some meaning to an angel, like Lucifer rising, or something big happening in Heaven. It wasn't exactly encouraging that they hadn't seen Cas in weeks.

Maybe he should've called Cas after all. There was no guarantee though that the bastard would even answer.

"There's still a jar of holy oil in the trunk," Dean said, not that that was likely to be of much use but it made him feel better, knowing that they had _something_ over the angels. Aside from sex and awesome music.

They were coming up to the end of the paved path, no lights beyond it, and a beach made up of massive jagged stones. Definitely not natural, but not exactly ugly in the evening half-light. There were less dead fish here, and the water looked eerily thick and black. Dean was sure it should have been reflecting the sunset or something the way you always saw in vacation photos and magazines. Still, this was Chicago, not some tropical island, and no matter how far Dean and Sam had walked away from the main tourist area there was no escaping the orange glow of cities everywhere and the distant sound of rumbling traffic.

"We could be out for a romantic stroll," Dean teased. It felt good, walking beside his brother, discussing a case like they’d done a thousand times before. It was so familiar, and something Dean had missed when Sam hadn’t really been Sam but some weird-ass mannequin of a man. Working cases with Sam without his soul had been like walking around with some poor imitation of something you loved that just reminded you all the time of what you’d lost.

"Yeah," Sam snorted, "Great place to bring a date, what with the fragrant night air."

Dean laughed, because before, even when they had work to do there had always been time for this kind of thing with Sam. Not so much with soulless Sam, who was all about the winning and didn’t seem to care at all about anything in-between. Fuck, it had been so long since they'd messed with each other like this. There was always some shit in the way, something _wrong_ , and just for once, here beside a dead-fish clogged late in an early spring heat wave that would've made any desert proud, it felt good to have his brother back.

“It suits you,” Dean threw back. “Compliments your own fine odour.”

“Are you saying I smell bad?” Sam stared at Dean incredulously as they walked. “What are you, five?”

“Hey, I’m just saying it how it is. I’m the one whose gotta get in a car with you.”

There was nothing to see out here that Dean could tell. He could barely stand the stench, and would've killed for a cold beer, but even so, Dean was reluctant to let this moment of maybe-sorta contentment go. The sun had nearly set though, and they hadn't brought flashlights with them, and Dean didn't want to chance breaking his ankle on the rocks. That would just be embarrassing.

He was about to call it a night and suggest they head back to the impala when Sam stopped, shading his eyes from the low glare of the evening sun with his hand.

"You see that?" he asked, pointing ahead of them.

Visibility was bad with heat turning the air into hazy mirages and twilight casting long shadows over the beaches and the lake's surface, and for a long while Dean couldn't make out what Sam was looking at.

When he saw, he knew what it was- who it was- instantly. No matter how far away or distorted there was no mistaking that trench coat, nor the awkward, statue-like way of standing Cas always had.

"Is that who I think it is?" Sam asked.

"Oh, yeah," Dean said.

Sam frowned. "This can't be a coincidence, right?"

"Doubt it."

It couldn't be a good sign that Cas was already here. It meant bigger, badder things.

They watched Cas not move, at all, and with the added weirdness of the dead-calm of the like it looked as though the whole world had been put on hold. From what Dean could tell, Cas was staring out over the lake, fixed in place, and it didn't seem like he’d noticed them. It didn't make sense. If Cas was looking for them, surely he would've contacted Bobby, or just appeared right in their faces. Not half a mile away, in the dark, on sharp and pointy rocks brooding like Batman.

Sam must have thought it weird too because he sounded uneasy when he said, "You think we should call him?"

"I guess," Dean agreed.

If Cas was here alone, on his own business, that just made this whole situation freakier.

Neither of them ever asked what Castiel did when he was away doing his angel-business thing, and he never offered any explanations, but that didn't mean Dean never wondered. It didn't seem likely that Cas was just here because he happened to like the view.

He called, "Cas!" and again, "Castiel!" when Cas didn't respond. To Sam, Dean said, "He seem out of it to you?"

It wasn't like Dean was worried or anything, because Cas was a big-shot angel and could take care of himself, but there was definitely something not quite right when he couldn’t even hear them shouting. Cas continued to look out, unmoving, and maybe it was just ego or whatever but Dean was sure that Cas would never just ignore him. Them.

"Cas!" he called again. "Get your ass over here!"

That, at least, got Cas's attention and he turned slowly towards them. It was too far to see clearly, to know if it was just his imagination, but for a second Dean would've sworn Cas didn't recognise them. Even though Dean was sweating like a bitch, skin overheated and uncomfortable, the air stagnant and heavy and cloying, in that second Dean still somehow managed to feel cold. Then the look- if it had ever existed- was gone, and Cas was shoving his hands into the pockets of his coat. Before Dean could think anything else of it, Cas was standing right in front of them, eyes on Dean, serious and familiar.

"Dean," he greeted, then tilting his head to the side, "Sam."

All the times Dean had seen Cas in recent months he’d been short-tempered, like someone was continually on his case. He was always in a hurry, only ever deigning to give them a couple minutes and explaining exactly nothing. Now though, Cas had a sereneness to him, if a confused one, like Cas didn't quite know what he was doing here.

Sam looked at Dean, raising an eyebrow and glancing towards Cas. Dean shrugged, because the hell if he knew what was up with the angel. Things hadn’t been so good between them recently, to the point that Dean sometimes had to wonder if they were even friends anymore. Most of the time he got the impression Cas didn't think whatever was going on with the angels had anything to do with him or Sam. On a generous day Dean would allow that maybe Cas didn't want them involved in something he thought was way beyond them, but even that pissed Dean off. Lucifer had to be the biggest of them all and Dean and Sam had taken him on. It was like Cas didn’t think them capable of handling themselves which was bullshit. If Cas would just _talk_ to them sometimes, let them know the Earth wasn't about to get wiped clean by psychotic angels, that would’ve gone a long way to making Dean less irritated with Cas.

"Something up?" Dean asked.

Cas hadn’t, at least, just gone and disappeared on them. There was that feeling again that something was messed up, but if this was some big Heaven thing Cas certainly wasn't acting all up-in-his face, emergency, gotta act now, like he usually was.

For a long moment Cas didn't reply, almost like he wasn't sure how to answer.

Still in his suit and trench coat, just looking at Cas made Dean feel hot, and not in a good way. The confusion on Cas’s face made him frown, and yeah, maybe he felt a little concerned.

"I was drawn here," Cas said finally, which answered just about nothing.

By now the sun had almost entirely set, and they still didn't have any damn flashlights on them.

Dean crossed his arms. With this unending heat, with Cas being his usual incomprehensible self, despite the weirdness of it all, he couldn't be blamed for being on a short fuse.

"Yeah? You wanna explain what that means?"

Another long pause and Castiel shook his head slowly, unsure.

"These omens." Cas turned his head to look out over the lake again, not at the sky but at the water and the fish. "They are familiar."

"So they are omens," Sam said. "We couldn't be sure if the heat was natural or, well, man-made."

"It is artificial," Castiel confirmed.

"You wouldn't know something useful like, what was causing this?" It wasn't like Dean had any real hope that he did, or that he would tell them even if he did, but it was worth asking anyway.

Predictably, Cas replied, "No." Then, with a look on his face Dean had never seen before, but was maybe somewhere between frustrated and preoccupied, Cas added, "But it is ancient. I'm sure of this."

"You got anything more specific?" Dean pressed.

"I think," Cas said, lowering his eyes to the ground in the way he always did when he told them something he didn't think they wanted to hear, "I think I have seen this before, a very long time ago."

Sam glanced at Dean again, surprised and uneasy. "How long ago, exactly?" Sam asked cautiously.

Cas closed his eyes, not looking at all happy. When he thought about it, Dean realised neither he nor Sam knew how old Cas- _Castiel_ \- really was. It had never come up, and had never really seemed to matter. Dean found himself curious though, at the idea of Cas, centuries ago or maybe even more, roaming about Earth. What had he been like, back then? What vessel had he had? What had _Cas_ been like? It was freaky to think about.

"In your years," Castiel said, not opening his eyes, "Perhaps six thousand have passed since then."

And fuck, but there was a difference between knowing in a general all-angels-are-old way and Cas coming out and saying it outright like that.

Beside him, Sam whistled in awe, probably forming hundreds of questions to ask Cas about history and time and whatever else his brain could come up with. There was something about the oppressive heat though, and Cas's _lack_ of urgency, that made Dean sure they didn’t have much time to, that they needed to hurry the fuck up and solve this case. Not least because he didn’t think Chicago could take much more of this heat wave without going completely crazy.

"I take it," Dean said, taking in Cas's sudden sadness, obvious even in the semi-darkness, "Whatever happened didn't end well."

Cas hunched his shoulders, pulling his coat more tightly around himself as though he were cold, and said, "I don't remember. I should remember. I don't."

Something that could make an angel forget; yeah, this was not going to end well at all.

***

They found a motel outside the city because fuck if Dean was going to stay in the claustrophobic oven that was Chicago right now. It wasn’t much cooler, still no breeze, but at least they didn’t have to deal with the pungent dead-fish smell.

The first thing Dean did when the door was shut behind him was to turn on the air-con and crank it up to maximum. It was like fucking _heaven_ \- the good kind, not the kind filled with assholes- and for several minutes Dean laid on the bed he’d claimed as his own, arms spread wide, and gloried in the feel of cool air. He would worry about how gross he smelled and how grimy he felt later. For now there was just him and the air-conditioning.

And a pensive Sam And Cas hovering by the door looking ill at ease. More ill at ease than usual.

It wasn't late, but Dean still felt tired, and Cas looked about as good as Dean felt.

There'd been silence in the car on the way to the motel, Cas in the back because Dean didn't want him flying off somewhere when it was pretty clear he had something to do with this case. He thought he’d have to argue and threaten and yell at Cas to stay put, because he always had before, so it was kind of disconcerting when Cas just got in the car without a fight. Sat in the backseat, from the way Cas stared at his knees, concentrating, Dean guessed that Cas was freaked out about having parts of his memory missing, because he would’ve been too.

Dean realised, not long into the drive, that he was checking on Cas pretty much continuously in the mirror. It wasn't weird, he told himself, because there'd been something wrong with the guy since the moment they'd first seen him. On the walk back to the car, sometimes it was like he didn't understand them. Not in an I-don't-understand-that-reference way, but in an I-don't-speak-English kind of way, sometimes answering them in some weird-ass language Dean was sure he’d never heard before, and Sam said sounded sort of maybe Persian.

The thing that was really getting to Dean though was how sometimes the look in Cas's eyes turned cold and distant, like he didn't recognise Dean or Sam anymore. It was the same look Dean had thought he’d seen before, when they first came across Cas, and now he knew it hadn’t been his imagination. This was Cas’s holy warrior look; righteous and single-minded and it was a look Dean hadn't seen in a long time. He’d kind of hoped never to see it again. The look reminded him too much of that time just after he'd been dragged out of Hell, and all the crap that'd happened. Maybe worse, Dean had never trusted that Cas. Right now Dean didn't even know if he could trust _this_ one.

Whatever was going on in Cas’s head came and went, from what Dean could tell at random, and right then Cas was looking around the room without much interest. The room was the same as a thousand others they'd stayed in so Dean couldn't blame him for that. Cas looked like shit, and even if Dean was pissed at him for all the ignoring and the dickishness, Dean wasn’t about to forget all the times Cas has helped them.

"Dude, sit down." Dean sighed, giving in to the inevitability that sooner or later he had to get back to the case. He sat up, patting the bed beside him. It was a big bed, and would be way more comfortable than the hard-looking chair that sat in the corner. If he was being honest, Dean wanted to keep Cas close too, because he was restless, his eyes darting around the room, taking his hands from his pockets before sliding them back in, and Dean was nervous that Cas was about to bail on them.

Across the room, Cas hesitated before moving closer, and even then he didn't sit down.

"I don't like this," he said, and squeezed his eyes closed like he was in pain, suddenly swaying on his feet.

Dean stood up instantly, hands gripping at Cas's biceps, holding him steady. "Hey, hey. It's cool. Just sit down."

He tried pushing Cas down on to the bed but his body was as immobile as stone. "Turn off the mojo, man," Dean complained, and Cas pulled a confused face that made Dean think he hadn’t even realised he was doing it.

Cas turned pliant so quickly Dean almost overbalanced, but managed to catch himself at the last second and easily pushed Cas down to sit.

"Okay," Dean said. He left a hand on Cas's shoulder, hoping it would keep Cas with them. "Tell us what you can."

Cas just shook his head irritably. "I can't tell you what I don't remember."

Dean ignored the tone and the way Cas opened his eyes to glare at Dean.

"You said this was something from ages ago, so when? We don't need specifics just... you have to remember something to know that there's something to _miss_ , man."

Lowering his head to look at his lap, Dean guessed that Cas was trying to concentrate, or focus, or something, and there was quiet in the room. On the other bed, Sam was booting up his computer. Unhelpfully, he just shrugged when Dean looked over at him for some help. Sam was definitely wearing his worried face though.

"Before," Cas decided on eventually. "After creation, but before."

This, apparently, was a satisfactory answer for Cas because he looked up at Dean expectantly, as though he was supposed to have understood that. As though, _sometime after creation_ had narrowed it down any.

"Before what?" Dean tried patiently. He realised he was treating Cas like one of the victims he and Sam spent half their time interviewing, and felt like a dick for it.

"Perhaps, I think, definitely before the birth of the Son."

It wasn't right, the way Cas hesitated over words. He never hesitated over words.

"What-"

Sam cut in, "I think he means Jesus, Dean. BC." Sam looked at Cas for confirmation. "Right?"

"Yes."

The air conditioner was loud in the silence that followed, and Cas's face was blank, like he had nothing more to offer. This was getting them nowhere. Dean was just about to try a different tack, maybe start with whatever had drawn Cas to the lake in the first place, when Cas stood up abruptly, his head whipping around to face in the direction of the door, his eyes turning distant.

"More have been taken," he said, or more like _intoned_. It was a voice Dean had never heard Cas use before; something commanding and imperious like you might expect an angel to speak rather than Cas's usual hoarse rumble.

“More people?” Sam shoved the computer off his lap and came over to stand next to Cas. "What’s taken them?"

"It makes no difference," was Cas's reply, still in that weird voice. He was looking at something beyond the door, at something neither Dean nor Sam could see. "You can't stop it. I have told you this."

"No," Sam shook his head. "You haven't. What is-"

Suddenly, Cas slumped, sitting heavily back down on the bed. He scrunched his eyes closed and reached his hands up to press fingers against the side of his head like he had a headache. Whatever had come over Cas- maybe some memory or some kind of possession- had passed.

“Cas, open your eyes,” Dean insisted, taking Cas’s chin and turning his face towards him, needing to be sure Cas was himself.

Obediently, Cas opened his eyes, blinking at Dean and asking, "What happened?"

Somehow, Dean knew this was their Cas; staring, familiar, bad-tempered Cas.

Sam had his hands on his hips and was frowning down at Cas. "You don't know?"

"I think I-" Cas broke off, started again more urgently, "There is a creature. It will take more. Or it already has. We must return to the lake."

"We just got away from there," Dean protested, thinking of the way the motel had transformed into a cool haven and outside was a burning, stinking, city of misery. "We don't know what we're looking for. We don't know _where_ we're looking. You know how big that fucking lake is?"

"I know these things," Castiel said impatiently, but he didn't sound all that convincing. "We must go _now_."

"If you _know_ ," Dean sniped, "then tell-"

But before he was able to get out the rest, he felt Castiel's fingers pressing against his forehead and _oh fuck no_. The next thing Dean knew there was that uncomfortably familiar lurch of angel transportation and the Dean was falling, hitting the ground hard. There hadn’t been far to fall, but Dean’s unbalanced, tripped, his ankle giving way with the unexpected appearance of rough, uneven ground under his feet, and he fell back painfully onto hard stone.

He lay where he’d fallen for a few moments, trying to adjust to the sudden sweltering heat and to the darkness around him. And there it was again; the sickly smell of rotting fish. There was no doubt he was back at the lake again and Dean decided he was going to fucking _throttle_ Cas.

Somewhere close by there was movement, and with reflexes developed over years of hunting Dean was up and on his feet in seconds, ignoring the uncomfortable throbbing in his ankle, taking in his surroundings and looking for threats. His hands automatically sought out a weapon that wasn't there.

He stood on the edge of some kind of thick forest, a rocky beach stretching away back towards the lake. Dean was pretty sure the shoreline around Chicago didn’t look like this.

Not far from him, Cas was picking himself up off the ground, dusting down his coat and looking around with slow careful movements until his eyes met with Dean's. Dean's _glare_. It was a lot darker here- wherever they were- than it had been earlier walking along the shoreline, but Dean could see enough.

"I didn't mean to land that way," Castiel said, sounding apologetic.

"But you did mean to bring me here," Dean retorted angrily.

"It was urgent we-"

Dean interrupted, "I'm _unarmed_ here, Cas. I can't just burn the sockets out of my enemies’ eyes."

"There was no time, Enki," Cas said. He had that distracted look again, but Dean hadn't missed the fact that he was breaking into some goddamn foreign language again. Dean did not fucking like this one little bit. Being out on a hunt was bad enough, but out on a hunt with no weapon and an angel having some kind of mental breakdown was not Dean's idea of a good time.

Then, Cas said, "Where is your brother?"

"My- you brought Sam with us?"

Dean scanned the area more closely, swearing and cursing and trying very hard not to get really fucking angry at Cas. He needed to calm down, Dean knew that. There was no time for blame or arguing or shit like that. He needed to concentrate, but it was so damn hot. Sweat had already started to gather at the base of his spine, his jeans heavy and restrictive. At least, Dean thought, he hadn't taken his shoes off back at the motel. That would really have sucked.

"Sam?" he called, and started picking his way along the line of trees, peering into the dense forest beyond. It was almost impossible to make out anything inside the forest.

"He should be here," Cas said. "I brought him here."

"You also missed the fact that the ground was two feet lower than you thought it was," Dean pointed out pissily. He called out to Sam again and was relieved as hell when Sam yelled back.

"Here,” he called. “Dean, I’m here!”

Dean still couldn't see him, but at least he knew Sam hadn’t broken his neck or been eaten by a bear or been de-atomised or something by Cas’s broken mojo.

"Where are you?" Dean yelled.

"In a forest?" Sam replied, like the answer should be obvious. "I can't see you guys. Cas, your aim needs work."

"Tell me about it," Dean muttered, then, "We're out on a beach or something. You can't be far."

Sam sounded pretty freaked out when he called back, more quietly, "It's really dark in here."

Turning to Cas, Dean asked, "Can you find him?"

He was wary to ask because whatever was going on with Cas was screwing him up, but he didn't want to leave Sam alone in the creepy ass forest one second longer than he had to.

He was sure, at least, that Cas could see in the dark.

Nodding in reply, Cas took off at a fast pace straight into the forest.

"Wait up," Dean called, and followed at a painful jog. His ankle was going to sting like a bitch after this.

Deeper into the trees, Dean kept close to Cas. It was almost pitch-black, worse than Dean had thought when he’d been looking in from the outside, and the ground was way more uneven than out on the beach, cut through with thick tree roots and dead, fallen wood. The air was stiflingly close and unnaturally thin, like half the oxygen had been taken out of it.

He couldn't hear a single animal.

Dean found himself whispering to Cas when he asked, "Whatever this thing is, it's here isn't it?"

Cutting a sideways glance at Dean, Cas nodded once, said, "Yes," then added "Sam is close."

When Sam called to them not long after though he sounded miles away, voice echoing impossibly through the thick forest. "Are you guys close?" he yelled. "'Cause I should tell you, I don't think I'm alone in here."

"Fuck," Dean swore. To Cas he said, "We need to hurry up. Can't you zap us there?"

"I wouldn't like to risk it." Cas narrowed his eyes, maybe trying to see better, maybe in frustration, but he took Dean's wrist and sped up his pace, veering away in a different direction from the one they'd been headed in. "I'm sorry," he said. "I think- I remember-” Cas shook his head, took a breath and wasn’t that just a weird thing to see. “We go around."

"I don't even know what the fuck is going on," Dean hissed in reply. "You haven't told me anything. Jesus, it's the same every fucking time."

Dean knew it wasn't the time to be bitching, but Castiel's cryptic half-explanations were getting really old. He knew something was wrong with Cas, and would like to have believed if he was himself- if he wasn’t messed up- he wouldn’t have done this. It was difficult though when Cas rode in and out of their lives like he didn’t give a fuck. Sometimes Dean didn’t think he knew Cas at all anymore.

"And I'm still unarmed," Dean complained. He had a knife strapped to his ankle still, sure, but it was _small_. It wasn't a great stretch to think that anything that could take seven or eight or ten passengers from a ship before they could make any kind of call for help had to be fast, and it had to be big.

Beside him, Cas reached into his coat and pulled out his sword, holding the hilt out to Dean. It shone a strange dull blue in the darkness. "Take it," Cas said.

Dean looked at the sword, looked at Cas. "Seriously?"

"It's true I brought you here unarmed, unprepared. It was thoughtless of me. I don't know why I did it. With this you can defend yourself against anything."

"But then _you'll_ be unarmed," Dean pointed out. As much as he wanted to take the magical angel knife, Cas was the fastest of them, the strongest, and it seemed obvious that he should keep his weapon. It felt kind of weird and intimate to take Cas's sword and Dean wasn’t even sure why. And he was definitely not thinking of Meg and how she’d taken Cas’s sword. Dean wasn’t. Not at all.

Several times before Dean had taken other angel's knives too and he’d never thought twice about it then. But this was _Cas's_ , and Cas was pressing the cool rounded handle into Dean's hand.

"I have other weapons at my disposal."

Cas turned away, dismissing any further argument on the matter. It wasn't that Dean didn't trust that Cas could take care of himself, he just didn't know what Cas was and wasn't capable of any more. He'd seen first-hand how Cas's mojo was off. Dean got the feeling Cas wasn’t sure of himself either.

It occurred to Dean how Cas had said he could _defend himself against anything_ with his knife. The implied _including angels_ was something Dean was not going to consider in relation to Cas.

Around them was eerily quiet, the world filled with shadows and shapes Dean couldn't quite make out. The suffocating heat was worse among the trees, the stench of decaying plants and trees added to that of decaying fish, and somewhere behind it all the distant smell of corpses. Somewhere close, Dean was sure, and Jesus fuck Sam was out there.

As they picked their way carefully through undergrowth, around thick, old trunks, Dean leaned in close to Cas, not wanting to draw attention to them but needing to hear that Sam was okay. "I need to call to Sam," he said, and was relieved when Cas nodded in agreement.

It didn't exactly make him feel any better when Cas told him, "It will know we are here anyway."

"Shit," he swore, then in a louder voice, "Sam! You still there?"

His stomach went cold when he received no reply.

"Sam?" he called out, louder this time. Silence.

Dean turned to Cas, demanding, "Where the fuck is he? Can you see?"

"I thought he was-" Cas began, but cut himself off. He stopped moving, looked cautiously around, frowning again in a way that Dean recognised as _possibly starting to freak out_. Fuck. _Fuck._

Dean could kind of work out the direction Sam's voice had come from before, and even if didn't have a flashlight, he couldn't just stand there, not knowing and not doing nothing. Beside him, Cas didn't seem to know what the fuck was going on so he just ran, yelling back at Cas, “His voice came from this way.” Cas would follow, Dean was sure, and he ignored Cas's calls to stop, to turn back, to slow down.

As he ran Dean kept his eyes sharp, kept Cas’s sword up and ready, seeking out evidence of Sam, or of something supernatural lurking among the trees. He had to be nearby.

Whatever this thing was, Dean vowed, it had better not have hurt Sam. There had to be a good reason for Sam not calling back. Maybe he was hiding out. Maybe he'd sprained his tongue. Sam would be okay, because he could look after himself and Dean would _know_ if something bad had happened to him. Nothing bad was going to happen to him.

If Cas was right and this creature knew they were here anyway, Dean reasoned, it wouldn’t make any difference if he called out, so he yelled Sam's name.

He ran as fast as he could, called out, but in the darkness all the trees looked the same, every direction no different from any other and Dean came to realise that he couldn’t tell anymore where Sam's voice had come from. Slowing down, Dean turned to look behind him and Cas wasn't there.

It was then that Dean saw movement; a slow sliding of shadows to his right, then in an instant it was gone, then movement to his left. He could hear it, not steps but a continuous crushing of bone-dry leaves and a snapping of branches, like the thing was rolling along on wheels.

Definitely not Cas.

Dean could sense it watching him, the feel of its gaze cold down his spine. The smell again, more intense than ever, decaying, bloated, fish guts, could only have come from this thing.

"Fuck," Dean whispered under his breath, hands grasping tightly around the hilt of Cas's sword. The cool weight of the metal was a welcome reminder of the strength of the weapon in his hand. Then, he saw its shape; its shadow a large, looking bulk that seemed bigger than some of the trees.

The shape and shadow and sound darted to his right, to his left, behind him, now in front, and Dean thought maybe the thing was just jerking him around for sport.

Sweat dripped into his eyes and Dean wiped it irritably away, wishing for a fucking breeze or maybe one of those little hand-held fans. _Anything_. Wishing the thing would just attack already because this stalking thing the creature had going was fucking annoying.

Into the darkness Dean found himself muttering, "Where the hell are you, Cas?"

 ****

2.

The moment Enlil announced he'd found something- a summoning spell hidden, obscurely coded on one of the oldest tablets in the libraries of Nippur- Enki had known it wasn't going to end well. The priests had sliced up the entrails of a goat, burnt and mixed with foul smelling spices, and declared that this was the only way.

For a long time Enki had suspected that the priests’ _omens_ were bullshit, and from the worried looks on their faces Enki guessed they were just as scared and clueless as everybody else about what was happening around them. Enlil's spell was the first solid idea anyone had come up with. It was hope, and the priests clung to it like it was a certainty.

Five days later in the halls of the Temple of the Earth at Girsu, the priests there slaughtered another goat, ripped out its insides and came to the same conclusion; this spell could save them. Enlil bought it all, and looked at the stars with the astronomers and spoke with the oracles and Enki took to pointedly _not_ following him around. His brother knew his stuff, sure, but the priests had taken to looking at Enki like he was one of the idols they worshipped. It was creepy and disconcerting and at the first sign of Enlil being finished with whatever the hell he was doing Enki packed them up as fast as he could and demanded they leave. He wanted out of the oppressive smell of incense and oils and the priests' watchful gazes. Enki didn't know how Enlil could stand it, had never really understood it, but his brother had always seemed to somehow fit in to life at the temples in ways that made Enki think his brother should've maybe become a priest. It would certainly have been a better life than what they had. It had to be the libraries, Enki guessed. Enlil had always preferred to hang out among rows and rows of dusty tablets rather than on the road. He'd always been good at learning, and was as comfortable walking the steps and the palisades of the Great Houses as he was wielding a knife against a demon. It wasn’t a surprise to Enki, then, when Enlil protested the hurrying, didn't want to leave without reading more and something else and some other crap, but as far as Enki was concerned they'd learned all they could. It was time to move on.

"I don’t know what your problem is," Enki said as Enlil dragged his heels and sulked like a child. "There are more things to read in Eridu." They passed through the city gates, guarded on either side by the great guardians, venerated and adored, but to Enki little more than a waste of expensive stone and hours of labour. The spells chiselled into their sculptured lion bodies and the bones buried beneath the gate posts did more to protect the city than any fine carving.

Enlil still looked back longingly.

"You're the one who said we were _running out of time_ ," Enki reminded him.

Two days south the rains began to fall.

Up to that point it had been nothing more than heavy grey clouds in what should have been a clear sky but this turned to light rainfall, more welcome than ominous along the hot, dry roads. It was spring, the first month, out of season, sure, but not unheard of.

Except that it didn't stop, and the spring heat didn't chase away the clouds. Instead, the rain fell harder with every hour, turning the parched ground to thick, sticky mud.

Along the road there was no shelter, and nothing Enki and Enlil could do but keep right on walking, miserable and cold, the route increasingly difficult to follow as the rut created by hundreds and hundreds of footsteps was washed away, indistinguishable. The air smelled wrong, heavy with something Enki couldn't make out. Enki had hunted for as long as he could remember and trusted his instincts with his life- with his _brother's_ life- but this was something different. Something bigger. If there was one thing that Enki understood it was that this rainfall wasn't natural.

Every hut and house and farm they passed had earth freshly dug beside the doorways, roughly-hewn lions and spirits carved into walls, and red stains where blood had been freshly spilled across boundaries; the most basic protections from evil spirits and monsters. It was like everyone knew that everything was going to shit. They met no one on a road that should have been walked by traders and travellers and nomads. Not many would tempt fate, or whatever, out in this rain, and Enki couldn't blame them. Things hadn't been right for a long time, months of omens and weirdness building up to this.

They had seen spirits that should have gone on peacefully to wherever the dead went turned into vengeful, spiteful _Edimmu_ in the Foothills. They'd seen families torn to pieces, ripped apart with a ruthlessness and cruelty Enki had never witnessed in all his years of hunting. It had been a desperate fight to exorcise them, salting and burning the bones of pretty much every corpse they could dig up because there were so many of the damn things, no time to find the right graves, and none of it made any sense.

There were _Udug_ in the villages of the East, sly bastard demons with black eyes and a taste for malevolence. The land was soft and dark there and people were so well fed they could waste the surplus on making copious, pointless offerings to their gods. Enki and Enlil hadn't often found work with the farmers of those lands. It wasn't like there was much interesting to fuck up, or possess or whatever. But there was disease, and murder, and a child possessed who burned down the reed houses of the fisherman and all their stores. Enough that it would make for a hard, maybe fatal, winter.

There, the exorcism had been long, and Enki didn't think he'd ever poured so much salt and holy water in his life.

He should've seen it coming, should've expected that sooner or later they'd come up against something strong, something out of place, again. And four days out of Girsu, along the banks of the Western river, a _Rabisu_ set upon them, out of nowhere, not long past noon.

For a creature that was supposed to hate the daylight, that as far as Enki knew had always lurked in the shadows and darkness, the thing sure didn’t seem bothered by being out in the open. Enki didn't get the chance to berate himself for his lack of attention, nor time to wonder where the hell the thing had been hiding, before it's ugly-ass face was right up in front of him, trying to claw his eyes out. There wasn't time to even pull out his knife before he was being pushed back, _mauled_ , so all Enki could do was kick out, trying to back away, hoping that Enlil was going to _help him_ pretty damn soon.

The _Rabisu_ was doing one hell of a lot better on the waterlogged, muddy ground than Enki. Its long, ugly clawed feet were digging into the earth while Enki slipped and fell hard on his back as he tried to twist away from the thing’s sharp, poisoned teeth.

It was on him before Enki could draw another breath, sinking fangs as sharp and thin as needles into his shoulder and _fuck_ it burned.

He heard himself swear, and he cursed the gods and the guardian spirits Enlil believed watched over them because his arm was trapped behind his back where he'd fallen and he couldn't get to a single weapon. With his free hand Enki tried punching the thing's face. It hurt like hell, skin tough as leather, red and peeling like the skin off roasted meat, but it howled and rolled away. This close Enki could smell the sulphur, its putrid breath, and he turned away, gagging and clawing at the ground to put some distance between them.

His shoulder felt like it was on fire and not even the steady, cool rain falling on his skin made it any better. It was distracting though; something else to concentrate on, and after a time Enki could move again without wanting to fucking _die_. And Enki knew he had to get up. He could hear Enlil calling to him from somewhere close, or maybe far. It was hard to tell. Enki was still breathing though, so his brother had to be fighting the _Rabisu_ now, and Enki had to help.

All his life he'd protected Enlil- kept him safe, that'd always been his job- and Enki wasn't about to stop now.

Moving hurt like a bitch but Enki had had worse, much worse, so he gritted his teeth and pushed himself up onto his hands and knees. His fingers slipped in the mud and he had to shake his head to get the rain out of his eyes.

Standing carefully, because his balance wasn't quite right, Enki took in how far he'd been thrown, how close to the river's edge he'd ended up. The water flowed so fast it had turned almost to rapids and Enki had never seen anything like it except high, high up in the mountains. On any other day Enki would expect to see boats sailing up and down the river, big and small, fishermen, life, but there was none.

That was all shit to worry about later. Enki turned, looking for his brother and the creature, and seeing them up the bank- and fuck knew how they'd gotten all the way up there- he dug his toes into the ground and scrambled towards them.

Enlil was holding the creature off with their last skin of holy water and his knife, the flint already blunted by the monster's thick hide. Enki could hear the dull thud of the blade edge against hard skin. He was upright though, and Enki couldn't see any blood or gaping wounds so it wasn't even close to the worst situation they'd ever found themselves in. Except the _Rabisu_ wasn't tiring out and it wasn't shying away from the holy water as much as it should have, and its jaws snapped and spat like the thing was crazed.

The hot ache in Enki's shoulder promised to be one bitch of a problem later but there was no time to worry about it when Enlil was red-faced, covered in streaks of mud, and fighting off something Enki had once seen ripping the throat out of a lion. Feeling for the knife in his belt, gratefully finding it still there and not lost somewhere in the dirt, Enki drew the weapon and cautiously approached the fight, trying for surprise.

Even though Enlil hadn't made any move to acknowledge him, Enki knew Enlil was aware of what he was doing. To keep the creature's attention Enlil picked fights, drawing it around to face away from Enki's approach. His brother got in a lucky cut across its face and in response the _Rabisu_ screeched in pain redoubled its angry attacks, hissing and spitting when Enlil threw holy water at its chest and into its eyes.

Gripping the bone handle of his knife, Enki gauged the distance, the ground under his feet, the way Enlil dodged clawed fingers to the left, to the left again, before he launched himself at the creature's back. He put his whole body into pushing the knife straight up to the hilt into the creature's bared back.

Its scream was so loud that Enki's ears ached, made his fucking _teeth_ hurt. It lashed out blindly at him and Enki was forced to stumble back, away from the sharp claws, wincing as the movement pulled at his shoulder. Enlil took the opportunity to slam his own blade into the underside of the creature's jaw, and Enki could see its thick, black blood dripping down Enlil's knife and onto his hand.

"Enlil," he called urgently. "Let go of the freaking knife!" Because _Rabisu_ blood burned away at skin and flesh and that was not happening to his brother.

For once, Enlil did as he was told and withdrew, and Enki ran to his side, shoving his hand into the wet ground, washing off the blood with thick mud and puddles of dirty rainwater.

"I'm fine" Enlil insisted irritably, trying to take his hand back. He lifted his chin towards the creature. "Finish that thing."

The _Rabisu_ was writhing around in agony on its knees, head to the ground. Not dead yet, but dying.

There was none of its polluting black blood on Enlil's hand and his brother didn't look like he was in pain at all so Enki let him go.

Injured, the demon was more dangerous than ever and Enki moved closer carefully, knife outstretched in his hand. He wished he had arrows, but they'd lost those at some oasis weeks back fighting a _Gidim_ and they'd had nothing to trade for replacements. He wished he had salt, but the last of that had been used on a _Lamashtu_ hiding itself in the narrow streets of Uruk. All this work, Enki thought, and they had nothing to show for it except a shit-load of scars and a mostly dead family.

Sometimes he wondered why he did this. The monsters never stopped coming. As far as Enki could tell they had always been there and always would be. They were always stronger, faster, more ruthless than any human hunter could be. They knew every trick, learned to overcome every ward making it a constant battle to reinvent magic, remake traps, forge ever stronger weapons so that every single victory was a triumph. It was all Enki had ever known. This had been his life since he was a kid and now Enki couldn't imagine doing anything else; he wouldn't know _how_.

Hunters like them were always outsiders, pretty much unwelcome wherever they went unless there was something for them to kill. They were seen as harbingers even though they were always the ones left to deal with the monsters other people wouldn't even dare to get close to. Hunters, Enki guessed, represented all the things normal people feared. All that evil and all that was unnatural and different and wrong that normal people had no control over. Worse, hunters were almost always travellers and strangers, never stopping in one place too long, relying on the kindness and gratitude of others for food and shelter. They didn't always receive it. They weren't priests and they weren't soldiers and they weren't farmers. They certainly weren't kings. They had no place in anything normal, to most people almost as bad as the monsters themselves. More often than not they were feared, and that was how it had pretty much always been for Enki and Enlil. Dad had always said it would be this way.

Despite the suspicion and the distrust and the hostility, they did good. Who knew how many humans this thing had killed? There was something deeply satisfying in making sure it wouldn't be around to hurt anyone else ever again, the same way other monsters, other unnatural things had destroyed his own family. He wouldn't wish that on anyone. Sometimes, that was enough.

It made it simpler, too, that this asshole of a demon had bitten a chunk out of his shoulder, and spilled poisoned blood all over his little brother, and Enki was soaking wet and cold and in pain and tired. He was really tired of not knowing what the fuck was going on with the world. Taking all his anger and frustration, it was almost easy to slash and stab, driving away the creature's sharp nails, opening cuts along its arms even through its tough skin. Enki was sure the edge of his knife had long since become blunt, so he drove harder and deeper, scouring across the creature's back as it tried to twist away from him. It was one hell of a lot slower now, weakened and in pain, lashing out mindlessly most of the time. Enki hoped the thing wished it had never attacked them. Enki would make it wish it never had.

Thick, black blood stained the ground, mixing with the rain, spreading out in long streaks of poisoned water and Enki had to watch his step, trying to keep his bare feet out of its reach. This place, this ground, Enki thought, would become cursed. They had no more holy water to purify the soil. They had no images to bury.

Then, Enki heard Enlil call out, "Stop _torturing_ it and kill it!" and all Enki could think was that the fucker deserved it.

But they had things to do, places to be, more important than some lay-demon on the road in the middle of nowhere.

The _Rabisu_ , blinded by agony and a couple cuts to the eyes, was easy prey. It wasn't hard to get past its claws and drive a knife up into its heart. It screamed again, so Enki slit its throat, slowly, feeling it die under his hands, twisting the flint knife that Enlil had left lodged in its jaw.

Its cry cut off suddenly and the creature's body crumpled to the ground. Finally unmoving. Enki let the rain wash the black blood from his knife, passed Enlil's back to him when his brother came to stand beside him.

Looking down at the dead demon, Enlil said, "That was messed up."

Enki didn't deny it.

Maybe people had good reason to fear them after all.

***

In Eridu, Enki took one look at the knife, the expression on Enlil's face, the size of the bowl he held out and said, "This is so not a good idea."

He still felt crappy from the _Rabisu_ bite, his shoulder not healed and not healing no matter how many times the priests had washed and purified and wafted vile-smelling incense at the teeth marks. Like that would help. Enki'd told them a hundred times to give up calling on their gods. No one was listening. And if they were, they were probably laughing it up because in those last two days of the journey to the city Enki had seen more devastation and destruction than he'd seen in his entire life. And he'd seen some fucked up things.

The rivers were flooding. Fields and irrigation ditches and the flimsy reed homes of farmers and fisherman washed away. Crops had drowned and the people they'd passed had been hungry and panicked. In their desperation they prayed and begged and offered up more than they had. The priests were doing a roaring trade, hidden in their high, stone temples as the rain poured day and night, fat on the offerings.

Enki wondered if they actually believed any of the crap they spewed.

"What?" Enki snapped, eyeing the ritual knife, the sharpness of its blade, the way it was pointed at his hands, warily. "I haven't bled enough lately?" He knew how these fucking rituals always went.

Predictably, Enlil shushed him, apologising to the priests within earshot. It was at least some consolation that they looked about as happy about this as Enki did. The presence of hunters was, after all, polluting, and this was their most holy, most _sacred_ of temples. The walls, painted in blues and yellows, depicted gods Enki couldn't believe in but still somehow managed to hate. In the outside world, beyond these carved stones and flickering oil lamps, every day there were more stories of demons and monsters roaming and killing and being places they shouldn't. Enki wanted to be out there fighting them. Hunting, exorcising, killing the assholes, that was what he knew how to do, not this magic crap.

Enki was no idiot though. He knew there were too many. Picking off one demon at a time wouldn't do anything to stop whatever was causing the rain and the unprecedented influx of monsters.

This ritual, the priests said, more importantly _Enlil_ said, was the only way. Never had this been done before, the head priest told them. Never had anyone dared to anger the gods this way. Even the most powerful priest in the city, who commanded hundreds and never went hungry or knew discomfort, had red, tired eyes. His voice was hoarse from prayers and pleas, his white robes damp and more messed up than Enki had ever seen on a wealthy man before. He wondered uncharitably if his washerwoman was dead.

Despite all the assurances, the acolytes' _certainty_ that this ritual would work because the omens had revealed it to be the truth, the half-burnt guts of an ox had _decreed it_ , Enki wasn't convinced. It was one thing to summon a ghost, but a whole other game to summon a god. Or spirit. Or whatever was causing the rains. This was something exponentially more powerful than anything they'd ever fought before, and Enlil had insisted on minimal weapons. That would have bothered Enki more except they had no idea what would be effective against whatever it was anyway.

Even so, the priests meant to beg for mercy. Enki meant to kill the fucker.

In front of him Enlil nodded towards Enki's arm. "It has to be with this knife," he said. It was a beautiful weapon, inlaid with gold and so many precious stones that Enki's fingers itched to pocket them. Just one could keep them both fed for a month.

The priests' eyes watched them too closely, though, and all the riches in the world wouldn't matter if they were all dead.

Enki offered up his arm, let his brother cut deep. He watched as his blood flowed from his arm, streaming across his skin in trails of bright red, dripping into the bowl. Looking up, Enki met Enlil's apologetic eyes. Whatever. They'd hurt each other much worse than this before. It was a shitty thing to think, but it was the truth and Enki wasn't surprised when Enlil lowered his head like he'd understood exactly what Enki was thinking about; betrayal by his own brother. Sometimes Enki wondered if they would ever get over this. If they'd ever be able to trust each other the way they once had.

But now was not the time for any of their shit. Enki reached out with his uninjured arm and gripped at Enlil's wrist, because they needed to stick together on this one. He leaned forward, spoke in a low voice, "If this thing doesn't agree, Enlil, we _make_ it agree."

Enlil frowned, looked around them at the chanting priests, at the painted and carved walls of the temple, at the floor covered in spells, painted in lines of blood and frankincense. For a moment Enki though he was going to argue, but his expression was clear when he looked back. He nodded, certain and determined. No matter how much he might respect the gods, supposedly protective guardians to be loved and worshipped, if this thing turned out to be one of them it still had to be stopped.

It was unlikely any of their weapons would work on something so powerful, and Enki was pretty sure he'd never come up against something that could cause such widespread chaos before. It wouldn't be the first time the brothers had taken on a creature which should have been far beyond a man to defeat. The head priest, with shaking hands and a sickly look as though the gods were going to strike him down just for _thinking_ it, had seemed sure the spell would weaken this thing, so maybe they had a chance. Even if it was only a small chance, Enki would take it.  
The room was heavy with expensive incense and the acrid, unpleasant smell of burnt animal flesh and it was kind of hard to breathe. Enki's head felt weirdly light, dizzy, and he guessed that was because half his blood was currently filling the golden-coloured bowl Enlil was holding. He drew the bowl away and Enki clamped a hand over the wound, watching carefully as his brother carried the bowl over to the far corner of the room. A priest in fine, white linen crumbled something that looked like bark into the blood, and some other powders, water maybe, or oil, or both, all the time speaking in a low voice over the bowl, and even through the haze of the room Enki was sure he could see the mixture boiling and steaming.

The priest announced, "We begin," handing the bowl back and directing Enlil to stand beside Enki in the middle of the room and the carefully drawn summoning spells under their feet. Enki spared a doubtful look at Enlil, feeling a lot like a lamb going to slaughter.

He'd been told what he was supposed to do, but he still felt like an ass doing it. Since he'd first seen what magic could do, Enki had hated it. In his long experience nothing good ever came of it, and every time he felt the power of sorcery, the chanted cadence of a spell, the taste of potions, it made his skin crawl. Enki could already smell the stench of the unnatural, words he didn't know but could understand anyway ringing in his ears. Enlil held out the bowl to him and with Enki reluctantly took it, the stone sides warm. Slowly, Enki kneeled down, his knee clicking as he bent and Enki thought, _I'm getting old_. For a hunter anyway. People like him and Enlil didn't generally have long lives. Their dad had been an exception, until a demon had taken him too. So, maybe not such an exception after all, but he had lasted longer than most; long enough to see his children grown to adulthood and his hair to begin turning grey. An early death was the almost certain reward for all those who made it their life's work to fight against creatures a hundred or a thousand times more powerful than the quickest, cleverest, strongest of humans.

This was just another murdering bastard to kill, Enki told himself, and wouldn't let himself feel afraid as he dipped fingers into the bowl. He'd expected the blood to be hot where it was steaming but it was cool, almost cold, and he shivered.

Enki concentrated on remembering the words of the summoning instead, reciting the phrases he'd practiced with Enlil for days on end, careful to pronounce every sound, smearing the shape of a wide circle on the floor in front of him, grit scraping against his fingertips. He drew a line, cutting the circle in half and timed the words to his movements as he'd been taught. More blood on his fingers, then Enki formed the shape of letters in a language the priests said was more ancient than the Earth itself. The blood, the stone, his whole arm grew hot as he drew the foreign symbols, sharp edges, curves the shape of leaves. There was power in these words, or whatever they were, and Enki could feel it doing _something_.

As he spoke he came to realise that he couldn't hear anything else around him now except the sound of the heavy rain outside, running down the walls, dripping from the doorway, rolling away down the steps to the temple. It was so loud that he thought he could hear every drop of water, every time it hit stone or soil. It was almost like the priests around him- even Enlil- had stopped making any noise at all, not breathing or shifting or anything. All he saw were the shapes under his hands, two more lines, another curve. This was his blood, and to it Enki was binding something that could tear him to pieces, he could feel the tug of it, the way his whole body felt tied to the curves and lines on the ground. It was awesome power, but it was one he really didn't want. He'd asked a thousand times or more why it couldn't be Enlil who had to do this; why it had to be _him_. Enki was a hunter, nothing more. All the crap he'd done and all the things he didn't believe in made the priests' purifications seem like a joke. There was no cleaning his soul. He knew that there would be no resurrection for him when his life came to an end. Enki was under no illusions that there would be any comfortable afterlife for him, no matter how many lives he saved.

Enki spoke, and found he didn't have to think to speak the words and this too was probably magic bullshit. There was no doubt whatever he was doing was working; there was a sensation like rope tightening around his neck, his wrists, his ankles, with every breath, until he had no more breath left, and the circle was complete and the words were all said.

There was silence then, no movement. Sound returned, the world of the temple and the cold stone and his aching knees coming back into focus as though Enki had been in some kind of trance. Enlil was hovering close by.

Enki blinked, looked down at his hands, palms spread wide against the edges of the pattern of blood. He couldn't remember doing that, pressing his hands to the symbols. He didn't remember being told to do that. The spell should have worked, he thought. It _felt_ like it had worked but when Enki looked up there was the same haze of incense, nervous priests looking at each other, at the circle of blood, at him and nothing had changed. Nothing had appeared. With a certainty that Enki didn't understand he knew it had _worked_.

Beside him, Enlil was frowning down at Enki, looking uncertain like he didn't know if the ritual was over or if there was something he was supposed to do.

Then, from behind them the voice of one of the novice priests broke the silence. It was different though, voice deeper, rough as sand over stone, and he demanded, "Who has summoned me here?"

It was on instinct that Enki rose to his feet, ignoring the pull of strained muscles, and pulled his knife from its sheath, turning to face this unknown thing. No longer the priest, its eyes were too bright, too old, too _cold_ to be anything other than a supernatural being. Enki could feel the power of it, and the pull of it.

Enlil moved to stand closer. He hadn't drawn his weapon and Enki would get on his back about that later, but his stance told Enki he was at least cautious, ready to fight back if he needed to.

They'd both seen possession before and it looked a whole lot like this, even if the head priests and the librarians at Nippur and Girsu had been certain that no demon could control the rains. But if this thing was a demon there would be no begging it for mercy, or whatever it was the priests meant to do. No demon Enki had ever met gave a fuck about humans.

There was something though, some familiarity or instinct that Enki had gained from all those times battling demons, something that told Enki this creature wasn't something he'd ever come across before. It was freaky, too, the way it stared right at him. It didn't even blink. Worse, Enki couldn't bring himself to look away and Enki wondered if the creature was using some spell on him. From the way the creature looked at him, _into him_ , Enki had the impression it was reading his thoughts. Judging him.

Enki filled his mind with all the times he'd defeated monsters and demons, and thought, _I'll do that to you, asshole_.

The priest who wasn't the priest anymore titled its head to the side and narrowed its eyes and Enki knew the fucker had heard him. Enki's first instinct, what he itched to do, was to run the thing through with his knife, newly sharpened and a welcome weight in his hand, and worry about the rest later. They needed information, though. They needed to know how to stop this, and Enki didn't think it would be so easy as to kill the creature and the world would right itself. Nothing was ever that easy.

There was a tense silence like they were all waiting for the creature to attack, or speak, or do _something_. The way it stood, inhumanly still, unafraid and patient, Enki got the feeling the creature could outwait them all and then some.

"What are you?" he asked, because they'd never get anywhere if they all just continued to stand around staring at each other. Not even sure why he did it, Enki took a step forwards, his knife gripped tight and pointed towards the creature's stomach. The thing didn't move, nor look at all concerned, not taking its eyes from Enki's for even the shortest time. Enki didn't think it was breathing. The cloying smell of incense and blood made Enki wish he didn't have to either.

He was actually kind of surprised when the thing didn't laugh at him or growl or spit like most supernatural bastards he'd ever met- and killed- but instead replied evenly, "I am an angel of the Lord."

The words meant nothing to Enki. In all his years of hunting, an angel wasn't something he'd ever heard of but Enki could see Enlil out the corner of his eye looking taken aback, like he hadn't expected that answer. At least he recognised whatever it was they were dealing with.

"A guardian," Enlil said. "You're supposed to be guardians."

The creature spared a glance at Enlil, but kept right on staring at Enki when it said dismissively, "That is a human misconception."

"But you're not evil," Enlil persisted. "Why would you bring the rain? Why would you bring _demons_."

At that the thing turned its gaze fully on Enlil, frowning and somehow managing to look pissed without changing its facial expression at all. As freaky as having this unknown creature staring at him was, Enki liked it a whole lot better than seeing that creepy attention turned on his little brother.

"I did not bring _demons_." It pretty much spat in disgust. Weird, Enki thought, that it would deny this so vehemently. It had not, Enki noticed, denied bringing the rain.

"Whatever it is you're doing," Enlil shook his head, "there are more demons now then I've ever seen."

Enki kind of wished his brother would shut up because who the hell knew what this creature was capable of. He knew though that they needed to keep the creature talking. This was their chance and they had to find out what the fuck it had done. Enlil had called this thing a guardian, which made no sense at all.

"We're hunters," Enki added, "We should know."

Grey, inhuman eyes turned back to Enki and it was almost a relief.

"This I didn't intend."

Enki scoffed, incredulous. "Then what, exactly, _did_ you intend?"

"To follow my orders," it replied simply, like that answered everything.

"What orders?" Enki demanded. He knew nothing about the hierarchy of supernatural beings and cared even less. Finally the creature, the _angel_ , looked away, turning its head upwards towards the ceiling as though seeing beyond, listening to something they couldn't hear. Maybe it was.

When it lowered its head again, Enki remembered the young, unlined face of the priest and found nothing of him in the face looking at him now. Everything about it was so obviously something else, something other, that Enki wanted to demand to know what had happened to the kid being possessed. In all his time, Enki had never seen anyone come back from being possessed either alive or sane.

"That is no concern of yours," it said.

"I think it fucking is." Again, Enki didn't know why he did it, because no way was he even remotely going to intimidate this thing, but Enki took a step closer again, lowering his voice. "It's my concern when you're fucking with my world."

For a long time Enki didn't think the creature was going to answer him, its eyes reading him, searching him, looking for something, but it surprised Enki again by agreeing, "Perhaps it does. I will seek revelation." With a rush of sound like beaten cloth and a cool wind he was gone.

The door was still shut fast, the high windows in the walls too small for anyone to escape through, and impossible so quickly. Enki spun around to face the remaining priests, pressed cowering with their backs to the wall, on their knees. "You said it couldn't leave," he accused.

The priests' faces were pale with terror and confusion and Enki was about to lay into them because he had not just given up a shit ton of his blood and resisted every instinct to salt and burn that thing to come out of it all with _nothing_. But then there was that same weird sound that had signalled the angel's departure. The lamps flickered around them frantically and suddenly the missing priest was in front of Enki again exactly where it had been before it had disappeared.

This time though it fell to one knee with a pained sound and for a moment Enki thought maybe the priest had been returned. Then their eyes met and Enki knew it was still the creature, its distant, old eyes full of rage. Rage, and Enki saw pain there too.

"What have you _done_?" it demanded. It was breathing now, laboured breaths like it had just run a long distance. It had its arms wrapped around it stomach. " _What have you done_?" it demanded again, and this time its voice made Enki's ears ache, the sound sharp and piercing like fury turned to sound.

"The spell," Enki guessed. "It binds you to me-"

"Undo it," the creature cut in. The sight of something so powerful brought down to earth like this gave Enki a weird sense of satisfaction. Now maybe they could get somewhere.

"Hey, it wasn't my idea. I have no idea how to undo it. You kind of left us with no choice."

"Choice? Neither of us has a _choice_. You will release me, human." It rose to its feet, wincing and trying to hide it.

"I told you I can't," Enki said. He hadn't even considered that he would ever need to break this spell. He'd imagined the creature wouldn't need to be released from a binding spell when it was dead.

Beneath his feet Enki felt stone tremble, the lamps flickering wildly. The shadows sprawling across the carved walls shifted and warped until Enki could make out the image of wings; huge, craning wings and Enki had never seen anything like it in his life. It would have been a lie to say he wasn't kind of awed, because it wasn't just that Enki could see them stretching, blotting out the colours of the wall paintings of gods and trees and worshipping priests, but he could feel them too, filling the room. And now he understood exactly what this creature was. He'd seen their images often enough carved into city gates and walls, painted on the sides of homes, their shapes crafted into idols and protective amulets and Enlil was right, they were supposed to be _guardians_. They were supposed to protect people. Even if he hadn't ever believed they were real, not really, to find out now that these guardian spirits existed but were actually murdering assholes was just confirmation of everything he had ever believed. Or not believed. That there was nothing out there in the world, or beyond, looking out for any of them. That there was nothing good in the supernatural.

In a thunderous voice the _guardian spirit_ ordered, " _Release me_."

Enki's ears ached and his eyes watered but he stood firm, found himself back in a staring match with eyes that didn't belong in such a young priest's body. "Bitching about it won't change the fact that I fucking _don't know how_."

The creature's eyes were filled with wrath and burned with anger and Enki thought, well at least the bastard could _feel_. He didn't seem so distant now.

Beside him, Enlil tried to sound conciliatory, saying, "Look, how about we all just calm down." He laid his hand on Enki's sword-arm. "Put the knife down, Enki." Enki took a moment out of his glaring to shoot Enlil an incredulous look.

"Seriously, Enlil?"

"Yes," Enlil hissed, "I have an idea, okay?"

It went against his instincts, but regardless of everything that had happened between them Enki did still trust his brother when it came down to it, and Enki sure as hell couldn't think of anything else that might get this creature to talk. To stop. Short of trying to cut its head off, and that seemed unlikely with the temple shaking beneath them and its voice alone capable of making their ears _bleed_. He could feel the warm wetness beneath his ears, could see red lines trailing down Enlil's neck. This, Enki thought, had better be a fucking awesome plan.

Not taking his eyes off the creature, Enki lowered his knife, and Enlil nodded and smiled tightly.

Turning to the creature, Enlil pleaded, "We'll make a deal with you."

Enki saw immediately that this was the wrong thing to say because the ground beneath them shook with new and more determined strength, the stone above them shaking loose dust, grinding together so loudly Enki was sure they were all going to be crushed to death.

"I am _not a demon_ ," it growled, and even if Enki believed nothing else he believed that much. "I don't make deals." It spat the last word like it was something distasteful and Enki really hoped Enlil knew what the hell he was doing. No one knew the limits of this binding spell; how much or how little this supernatural creature could do to the one he was bound to- in this case Enki, and fuck did he regret agreeing to this magic crap- or to anyone else around him. Behind him Enki could hear the other priests praying for forgiveness, for mercy. Enki was pretty sure this creature didn't have any.

"No," Enlil tried. "No, I didn't mean a deal like that." He held his hands out, palms up, as though he were praying. "We just want to know _why_ you're doing this. We want to know what we can do to stop it, to save the people out there who are going to die because of what you're doing. You can't expect us to just sit back and let it happen."

The room fell into a tense silence and Enki watched as the creature seemed to consider Enlil's words. It was with immense relief that the ground beneath them calmed and the dark shadows of the room receded, the pain in his ears gone and Enki could breathe again.

Enlil, Enki thought in awe, had somehow got through to this thing. It looked thoughtful, frowning as though undecided.

"These are my orders," it said.

"Orders from who?" Enlil pressed.

"Heaven," came the answer, and Enki thought, if that was true then they really were all fucked.

 **3.**

There was no point in running. Dean couldn't see much of anything and running around in the dark without any clue which direction was which and some monster at his back was not going to help him at all. It just made him frustrated, more turned around, so Dean came to a stop, thinking and listening and trying to work out where the monster was instead of letting it wear him down to be easily picked off.

There was no breeze and the air around him felt stifling and thick, making it almost hard to breathe. Dean couldn't hear anything beside the sound of his own breathing, the sound of his boots scuffing against rotting leaves and catching in undergrowth. No movement; no animals, no monster, no Cas and no Sam. It was like the world had been put on pause so that even the tall trees around him with their sprawling branches kept unnaturally still. Dean was beginning to think he was the only thing left in the world and it was creepy as hell. Something had to give sometime, Dean assured himself, and he'd long ago learned patience.

No matter how many times he'd called out to Sam and to Cas they hadn't replied and Dean just had to hope that, whatever this thing was, it hadn't gotten to them. He hoped they were hiding out somewhere, or had some awesome plan that was based on them being completely silent. He really fucking hoped.

As he'd moved through the woods Dean had seen glimpses of the monster he knew was out there. More like, he'd seen its shadow because it was incredibly fast, disappearing into the forest before Dean had time to turn and face it. He thought he'd seen eyes, yellow and huge, but not part of any face that Dean could make out. He'd seen what he thought was its tail, long and whip like, and he'd heard it lashing against trees, cracking trunks with a sound like a gunshot. Dean did not want to find out what it would feel like to have that thing hit _him_.

If there was one thing Dean was certain of, it was that the monster was messing with him, crawling in and out of sight. At least, Dean thought, if it was after him the fucker wasn't hunting Cas or Sam.

From somewhere to his left Dean heard the soft shuffle of leaves, laboured breathing like a heavy smoker's. Pissed and too fucking hot for this shit, Dean called, "You're supposed to breathe like that down the phone, asshole."

He'd learned very quickly not to try and follow the sound because there was never anything to find if he did. The creature was trying to wear him down, make him angry and frustrated and reckless and fuck if it wasn't working.

Dean had long since sweated through his thin shirt to the point where it clung to his arms and back. The palm of his right hand where he gripped Castiel's sword was wet, the weird cold-hot metal of the handle slipping in his hold. He was thirsty as hell, the heat getting to him in a way he couldn't remember it ever doing before. From what Dean could work out, the air grew heavier, like breathing in a sauna, the closer the creature came. Maybe it breathed fire or something, Dean considered. He was fairly sure it wasn't a dragon he was dealing with though. For all the build-up they'd been pretty damn lame when it came down to it.

Scuffling again, this time the sound coming from directly in front of him, and Dean hoped the monster was getting more bold, bored of this annoying game of hide and seek that was less seek and more wander around aimlessly and hope for the best. The waiting around had always been the worst thing about hunting for Dean; he'd always preferred the fight, not needing to think so much as just _react_.

Then, there was a sound Dean hadn't heard before that was something like a roar, deep and low, like stone shifting. It sounded like pain.

Dean hesitated for a second. It could've been some new tactic to draw him out, and he still didn't know what he was dealing with. But then he heard the sound again and this time it was closer to a scream.

Through the arching shadows between the closely packed trees Dean could just about make out movement somewhere ahead of him, not exactly close, but not far.

Then, from the same direction, Cas's voice calling, " _Dean_!"

He sounded out of breath, and that was weird and all kinds of wrong, enough that Dean took off running, frustrated that he couldn't move as fast as he wanted to because he still couldn’t see shit, but forward. His grip tightened on Cas's knife and he felt its welcome coolness against his palm. Something about the way he called his name made Dean certain that Cas was fighting the creature. He just hoped Cas had it together enough to not get himself killed before Dean got there.

He heard something smacking against a tree, a splitting and a sickening crunching sound that Dean hoped to hell wasn't _Cas_. Or, shit, Sam. After this, Dean wasn't letting the two assholes out of his sight ever again even if it meant chaining them both to the fucking Impala.

Branches cut at his face and arms as he ran, his ankle started burning again and Dean had forgotten he'd even fucked it up. He remembered now though. It hurt like hell.

Ahead of him, his voice closer now, Cas called again, " _Dean_!"

Dean kind of wished Cas was a little more expressive so he could work out if that was a _help me_ kind of call, or a _keep away_ kind of cry, or maybe a casual, _I'm just killing this thing, be right with you_. It was impossible to tell with Cas.

His life had taught him to always expect the worst so Dean pushed on, following the voice and the movement and another growl from the monster that shook the trees all around him, dispelling the last of the stillness that had pervaded the woods since Dean had split up with Cas.

He knew he was getting near because the heat wrapping around him was almost unbearable. It almost felt like his skin was going to start peeling off, his lips bone dry and the smell of singed hair filling his nose. There was that unmistakable stench of rotting fish, too, growing steadily stronger to the point where Dean wanted to puke. He pushed the discomfort away, all of it, concentrating on getting to Cas and killing this fucking thing. The one thing Dean wanted to do, to call back to Cas and tell him he was coming, was impossible with breathing so hard and his throat so dry.

Another few metres of crippling heat and putrid smell until Dean could just about make out a shape; a body almost as wide as Dean was tall, long and pitch black and winding through the trees. The closest thing to this Dean could think that he'd ever seen was a snake. Except this was a giant fucking monster snake with skin that looked cracked, like jagged, sharp stone. Dean had no clue how the thing could've stalked him, could've _hidden_ from him, without making hardly any sound at all. There were arms too, jutting haphazardly from the long body ending in wicked looking claws.

Dean couldn't see Cas anywhere, but he knew he had to be somewhere up ahead because he could hear him grunting with exertion, could see bursts of light that left spots behind his eyes. In Dean's experience that kind of brightness was something only angels could produce.

It was likely that Cas was up near the creature's head, and Dean ran, dodging the writhing body and the flailing appendages that Dean refused to think of as arms as best he could. He dodged around trees, fought his way through broken branches laying thick and _in his fucking way_.

The creature jerked its body to the side, and Dean had to stumble backwards to avoid it, almost falling over. Righting himself, Dean found he was face to face with a rounded, yellow hole in the monster's side. It blinked, skin rolling inside it and Dean realised that holy shit this was an _eye_. An eye set into the creature's body and it was looking right at him and what the hell kind of creature kept eyes anywhere other than a fucking face?

It threw itself sideways at Dean, movements more coordinated, claws reaching out with _intent_ now that it had something to aim for. Reacting by instinct more than anything, Dean managed to launch himself away from the creature's body before it could crush him, but the movement sent sparks of agony up his legs and into his spine and Dean cursed, stumbled and fell sideways where the ankle gave way.

Some shitty help he was turning out to be, but it was possible he was distracting the thing, getting the monster's attention away from Cas. Why he thought he'd be better able to deal with a giant slug-creature thing with what looked like an inches-thick impenetrable hide and _eyes in its body_ Dean had not a freaking clue.

Pain still spiking through his ankle, feeling dizzy and slow, Dean pushed himself to his feet. He could do this.

Ignoring the part of him that told him this was a really stupid idea, Dean surged forward, both hands wrapped around the hilt of Cas's sword, aiming for the eye. He drove the point right into the centre, the large black pupil watching him even as Dean felt soft, viscous flesh give under the blade.

The creature screamed, a high-pitched wail that hurt Dean's ears. Warm liquid poured over his hands, stinging. This up-close and personal Dean could feel the heat pouring off the creature's skin, like he was standing pressed up against a furnace. He heaved from the smell and Dean wondered if he'd ever be able to get the stench off of his clothes, now stained a sickly yellow. He wondered if he'd ever be able to get the stench off of his _skin_.

It was too late to worry about that now, so Dean tried to cut deeper, pushing his hand further into the flesh of the eye. Muscle contracted around his arm and was shoved viciously aside for his trouble and Dean found out exactly how hard the creature's skin really was. It felt like brick connecting with his body, immovable and _sharp_. The hard shove knocked the air out of Dean, sending him sprawling, the back of his head connecting with stone and tangled undergrowth. It left him dazed, thorns and branches pressing uncomfortably into his back. Then the tail, coming at him with a speed that seemed impossible for such a large creature and Dean barely had time to curl in on himself protectively, knowing this was going to hurt.

The hit never came. Instead, Dean heard the familiar sound of wings and then there was a flash of light so blinding Dean had to bury his head in his arm. It had to be Cas and thank fuck for that.

Around him, deafening, there was more howling and despite every long-learned instinct to look and see and find out where the threat was, Dean could do nothing but keep his head down and trust that Cas had his back.

Finally, when the light had faded and the noise had cut off, Dean cautiously opened his eyes to see Cas's back right there in front of him. There was blood streaking down the length of Cas's coat and that could not be a good sign. Dean hauled himself up to his feet, feeling the muscles protesting and bruises already forming on his chest and on his back. His ankle really did not like him trying to put any weight on it.

"Cas. You okay?" he asked, and gritted his teeth in irritation when Cas didn't reply.

Somehow, Cas's sword was still in Dean's hand, held tightly, even though Dean was sure he'd let it go when he'd been knocked over that second time.

The creature, at least, was backing away, slithering sideways in a way that meant Dean still couldn't see its face. The eye Dean had stabbed through streamed yellow-white puss, leaving behind a trail, and that was just too gross.

"We must leave here," Cas said.

As much as Dean would've _loved_ to high-tail it the fuck out of there, there was no way in hell he was going to leave Sam behind.

"No, we have to find-"

"We will," Cas cut in, and didn't give Dean a chance to say anything else before he had turned around and pressed cool fingers to Dean's forehead.

 _Again_.

In that last second before they disappeared, Dean saw the damage to Cas's face. His nose wasn't at quite the right angle, definitely broken, and from the swelling on the side of his face probably his cheek too. Cas's left eye was half-closed, the skin purples and reds and painful looking. There was blood on his forehead, trailing down to his neck, that oozed from a long, deep cut just below his hairline. It was bad enough that something was up with Cas's mojo, but this beat up Dean should never have agreed to let Cas fly anywhere, let alone with passengers in tow.

Cas, stubborn bastard that he was, didn't give Dean a choice. The next thing Dean knew there was an uncomfortable tugging in his stomach, like a fairground ride but a thousand times worse and not fun at all, that Dean recognised as travel by angel. And then, there was light.

It was so bright Dean had to slam his eyes closed. Not the same whiteness as angel light, but more like someone had flipped on the lights in the middle of the night. This was something that had never happened before when Cas had mojo'd him somewhere and Dean couldn't help but thing that something had gone _very_ wrong. Except then he realised they'd stopped moving. There was wind against his face and the warmth of the sun against his back and neck.

Wherever they'd landed, it was daytime.

Now he stopped to concentrate on his surroundings, Dean felt the rough grittiness of sand being blown into his face. Slowly, Dean opened his eyes, letting them adjust to the daylight and saw that they were in a desert; rocky, the sand almost white, stretching for as far as Dean could make out. There was no sign of any other life- nothing green at all- just endless blue sky above and gleaming sand around them, distorted by heat. No dunes, like he'd seen in movies. No oases. A flat expanse of nothing.

"What the fuck?" Dean demanded. He leaned his weight off of his busted ankle and watched as Cas blinked, eyes carefully surveying the area around them, not that there was anything to see. The blood on his face made him look some victim out of a horror flick, just a whole lot more confused and less panicked.

In the light of day he looked a hundred times worse, the blood bright red under the glaring sun. Cas's face was freakily pale and sickly-looking. There were cuts and tears in his coat at the shoulders, down the arms, across his shirt, and all of them bordered in red blood that stretched and spread through the fabric.

"Shit," Dean said. "Shit. Cas. You gotta take us back." He had to get to Sam. He got that Cas was fucked up, he really did. He wished there was something he could do, but he _had to get to Sam_.

When Cas met his eyes, they didn't look right; unfocused and distant.

"This is the-" Cas began, and his voice sounded all wrong too, formal and detached like Dean was a stranger rather than someone he'd known for years. Someone he'd fought with. So maybe things had been shitty between them lately, but never had Cas been this dismissive and cold.

"We left Sam behind. Take us back," Dean demanded. All he got in response was a blank look from eyes that were almost unfamiliar in the way they watched Dean, wary. It was like Cas didn't even understand him. So Dean grabbed Cas's arms, holding on tightly. Cas winced and at least that was a reaction. Something like emotion. Dean felt like a dick, because he didn't want to hurt Cas, and he didn't know why he wasn't healing, but he needed Cas to be here with him.

"Dude, come on," Dean urged. "This isn't where we're supposed to be. _Help me_." Dean knew he had to sound half-frantic, desperate, because he was. And it had worked before, when Dean had thought there was no hope and no escape and Cas was the only one who could save them.

For a long moment they just stand there, the wind around them, the sun burning them- not like Chicago because this heat was natural, not tinged with magic and malevolence. Here, the air smelled clean.

Dean resisted the urge to shout and bully and force, no matter how much he itched to _do something_. There was no getting out of there without Cas, no getting back in time to help Sam because it was pretty damn obvious they were the other side of the world, in the middle of nowhere with not even the vaguest signs of civilization in the flat expanse around them. Instead, Dean waited, keeping his eyes on Cas's, watching as they cleared and indifference slowly turned to recognition.

"Dean," Cas said, like Dean hadn't been standing right in front of him the whole time.

"Yeah." Dean loosened his hold on Cas's arms but didn't let go.

Cas looked at the ground, frowning. "I don't know why I'm here."

"We can work it out later," Dean tried to reassure him. "We need to go back for Sam."

"Sam," Cas repeated slowly, and his eyes widened like he couldn't believe what he'd done. "I left him."

In the next moment there were fingers pressed against Dean's head and the bright desert disappeared, instantly replaced by the humid, stinking forest and the dark. Dean never thought he'd actually be glad to be back in this place but he was.

"Can you tell where Sam is?" Dean asked. He couldn't see a fucking thing again. This time he kept a hold of Cas's arm, resolved not to let go anytime soon. It meant Dean felt it when Cas stumbled and Dean had to steady him. Not a good sign.

"An _Asag_ ," Cas told him, "always keeps a lair. That is where Sam will be." He sounded certain at least, refinding his footing and standing up straight. Dean's eyes were adjusting to the lack of light again though and he could see that Cas's wounds still hadn't healed.

"I will look for him." Cas pulled away like he was about to leave Dean behind and fuck that shit. He tightened his grip on Cas's arm.

"You're not going without me."

"I can look more quickly without you," Cas insisted.

"Yeah, if you had your head screwed on the right way, maybe. Last time you took a flight we ended up in the Sahara."

"We weren't in the Sahara."

"Whatever. You're not going without me." Dean didn't much like the way Cas was listing sideways and he liked even less the silence around them. It felt a lot like before, when the creature had been stalking him. "I still have your knife," Dean added, offering it up for Cas to take. It was weird, he thought, how he'd kept hold of it without even having to think about it. Without even remembering it was there most of the time. "Right now you look like you need it."

Cas looked down at his blade, somehow reflecting light that didn't exist, but made no move to retrieve it. "It wouldn't have helped. Keep it for the time being."

"I just-" Dean threw up an arm in surrender. "Fine. Okay. Jesus, Cas. Stop arguing with me and let's just _go and find Sam_."

Cas looked for a second like he was going to start another argument but in the end just shook his head. He reached out and laid his hands on Dean's shoulders.

"Don't blame me if this is unpleasant."

That, Dean thought, was more like the Cas he knew; bitchy and impatient and not giving a fuck. Dean was glad to see it, but then the world spun, turned wrong and upside down and Dean wasn't glad about anything. He was aware of brief seconds- maybe parts of seconds- where he stopped moving, before the world tipped again. He thought he saw flashes of water, beaches, homes with warm lights and grills in their yards along the lakeshore. Sometimes there was a hint of a breeze of gloriously clear air before it was gone and he was back to the stench of death and decay. Then there was damp too; Dean could feel cold water dripping onto his arm, heard echoes around him. The world became darker and darker and Dean tightened his hold on Cas's arm. He wasn't sure why but he had the impression they were travelling deeper every time Cas paused, further underground. He wanted to ask, but there was no time between one place and the next.

When Cas finally came to a stop, and _stayed_ stopped, Dean's stomach lurched and he was sure he was going to puke all over his shoes. Or Cas. And Cas would freaking deserve it.

"Asshole," Dean bit out. His voice sounded tamped down like they were in a small, enclosed space. Beneath his feet the ground was uneven and Dean leaned on Cas until he could orient himself, trying to work out which way was up and which way was down and where he could put his feet and remain steady. It was stiflingly hot again, and Dean missed the cold caverns he'd imagined they searched and the cool breezes he'd sometimes felt. He Wiped his forehead with the back of his arm, feeling the sweat there and trying to remember those little things like how gravity worked and how to breathe.

"I did warn you," Cas replied testily.

Unsurprisingly, the dark was absolute, impenetrable. Dean had to blink his eyes to be sure they were even open. He was aware he was clinging to the sleeve of Cas's coat but didn't dare let go.

"I can't see," Dean said. He wasn't going to be any kind of useful like this.

"I'm aware." Cas's voice was thankfully close, softer and apologetic and Dean was just glad Cas hadn't let go of him either because he felt as though he'd be lost in this hole forever without Cas's presence, his tight grip curling over Dean's shoulders.

"We're a long way underground," Cas told him.

"I guessed that much."

Cas ignored the comment. "I will give you sight." Like it was the easiest thing in the world, and Dean felt the pressure of fingers, pressed gently against his eyelids.

There was a weird itching in his eyes as though he had grit in them. Rubbing at his face sparked flashes of red and light behind his eyelids and when Dean blinked his eyes open he found he could see the walls enclosing him, the floor, Cas in front of him. It was like someone had suddenly switched the lights on again.

"Woah," he said, squeezing his eyes closed, trying to get used to seeing when his brain was telling him he shouldn't be able to. The expression on Cas's face, beaten and messed up, was worn and unhappy, but determined, and maybe even a little amused.  
"You're not-" Dean frowned, meaning to ask why the hell he still hadn't healed, but Cas turned away, cutting Dean off.

"The creature's lair is this way."

There were a shit ton of questions Dean wanted to ask- mostly boiling down to what the fuck was happening- but now wasn't the time. And Dean was just glad that Cas was more or less back to himself.

"We got a plan?" Dean asked, looking down at Cas's sword in his hand. The monster's hide had looked pretty much impenetrable, had _felt_ impenetrable, and with the mess both of them were in he didn't relish the idea of fighting it again. Not without working out what the fuck they were doing.

"We retrieve Sam," Cas said.

"The demon slug thing?"

"Is not here."

Dean didn't get how the monster could’ve stashed Sam somewhere underground and then gotten itself back to the woods for one more round with him and Cas all in the maybe twenty or thirty minutes between losing track of Sam and now. It didn't make sense. Another thing that didn't make sense.

"This way." Cas nodded ahead of them before moving away quickly.

They were in a narrow tunnel, way too small for the monster he'd seen to ever fit in. The jagged rock walls dripped with water, the ground made up of shallow puddles and loose stones. Dean followed Cas, wincing as the stones gave way under his boots and his ankle twisted painfully. As they walked, the path opened out into progressively larger tunnels that twisted and turned like hallways, descending deeper at a steeper and steeper angle so that Dean had to bend awkwardly, trying not to scrape his head on the sharp stone ceiling.

"You couldn't have flown us any closer?" Dean complained.

"No," was Cas's short reply.

Never with the explanations. Dean had never been able to decide if Cas purposely kept things from him, or if he just hadn't worked out yet that proclamations like that needed some kind of elaboration.

Because it was easier than thinking about Sam shut up down here for who knew how long, Dean decided to educate him. "You gotta give me more than that, Cas."

That ever-present smell of rotting fish, almost overpowering down here where the air was thin and stale, and the cloying heat were really starting to get to Dean, making him irritable and impatient. Or maybe that was just Cas, because somehow Cas always seemed to get under Dean's skin.

It took so long for Cas to reply that Dean thought he was going to have to ask again, but then Cas looked up to his right, then to his left, gaze running over the grey-brown walls surrounding them as though he were searching for something. He lifted his hand and trailed fingers lightly over the stone. "There are sigils embedded into these rocks," Cas told him. "They keep me... grounded, as you would say."

"All the way down here?"

There was something really wrong about that because what the hell would anti-angel symbols be doing in a cave deep underground somewhere beneath Lake Michigan that was inhabited by a slug monster?

"They're newly laid," Cas said. "It could only have been done by-"

Suddenly, Cas stopped dead, pulling his fingers away from the walls like they'd been burned and pressed his hands to his head like he was in pain. Dean took hold of Cas's shoulder and turned him to face him, to see what was wrong.

"Cas?" he called, and Cas just shook his head at him and bent forwards, his face twisted into a grimace. "Cas, tell me what's wrong? Is it the sigils?" He glanced at the walls around them, at the ceiling and the floor. Cas had _said_ they were there but Dean couldn't see them. It was possible, Dean thought, that they weren't real, that Cas as losing it again. That was the last thing they needed. "Cas?" he called again and Dean leaned closer to get a better look at him.

His vision was kind of messed up because there was no actual light source, which meant no shadows. Instead, the world was made up of flat colours that made everything look two-dimensional, like cardboard cut-outs. It was hard to tell if Cas was actually as pale as he looked or if it was just Dean's confused sight. What he could see clearly was Cas's nose bleeding.

"Shit," Dean swore. "Cas. You gotta tell me what's wrong."

Cas's eyes were still scrunched tightly shut, and Dean wasn't sure he'd even heard. Trying to get his attention, get some kind of indication that Cas was still in there he tapped his cheek lightly. "Hey, man, come on."

It was so fucking frustrating because all Dean could do was hold on to Cas's shoulder and wait and hope to hell that Cas snapped out of it. He didn't know where they were headed and there was no way Dean could leave Cas behind when he could feel the guy shivering under his hands. Dean curled his hand around the back of Cas's neck, shocked at how cold the skin felt. It wasn't something Dean would usually do, be this touchy-feely, but he couldn't think what else to try and it wasn't like there was anyone around to see them. It seemed to help too, because Cas leaned into the touch and the shaking subsided.

Cas spoke, grinding out a series of hard guttural sounds that Dean recognised from the language Cas had been speaking before, back at the motel room. Back when Sam was still with them. Fuck. Dean couldn't know for sure, but every instinct told him they were running out of time.

"English, Cas," Dean insisted, but got more of the same language, words that were clipped and angry-sounding and Dean couldn't work out if Cas was pissed or if that was just how the language sounded normally.

Not knowing what else to try, he took Cas's face in both his hands, tilting his head to get Cas to look up, maybe open his eyes. Cas's cheeks were ice cold too. "I don't understand you. We gotta find Sam. _Look at me, Cas_."

He shook Cas, not wanting to hurt him but needing Cas there with him, and _right the fuck now_.

Something must've worked, or maybe whatever had just happened had passed, but the deep lines of pain on Cas's face began to smooth away, and Cas's hands relaxed from where they'd been pressing ruthlessly against his own temples.

"Thank fuck," Dean swore, but didn't let go. He watched as Cas opened his eyes slowly, obviously still expecting pain.

"Dean," Cas said, blinking and sounding relieved.

"Yeah. It's me."

"My head hurt."

It was really damn good to see Cas's familiar, unrelenting gaze.

"I got that, yeah." Dean smiled, leaning away as Cas straightened.

"There is something wrong with me," he stated, his eyes narrowed like his head still hurt.

"I got that too."

Cas shifted uncomfortably and Dean realised just how close they were, and with Cas staring at him just how weird it was to still have his hands on Cas's face. Dean awkwardly drew away. "So. We should-"

Dean nodded his head towards the direction they'd been headed before Cas had his meltdown.

"Yes, of course. Sam," Cas agreed. He turned away, unsteady but upright and Dean stayed close. Cas reached up as though to lean his hand against the wall for balance but quickly decided against it, balling his hands into a fist and shoving them deep into the pockets of his coat.

"It was the sigils that did that?" Dean guessed.

Cas nodded slowly. "They were too familiar."

The reply didn't make much sense, but nothing much did right then and Dean didn't want to push when Cas already looked shitty and worn and close to falling on his face.

He changed the subject. "We close?" There was no need to specify to what because Dean knew that Cas would understand. They had to find Sam.

"We are."

***

In his life hunting monsters and demons and other evil supernatural bastards, Dean had spent a lot of time in dark places; in caves, wading through sewers, in dark cellars, in Hell. This, though, was something entirely new.

They were walking through a wide cavern, but for as far as Dean could see with his nifty angel night vision, from the ground to the highest point of the ceiling, every inch of exposed rock was covered in sigils and scrawls that might've been writing. A lot of it looked painted in blood.

The floor had turned increasingly pitted and uneven, and the continuous clambering was making Dean's sprained ankle burn. Much more of this and he was sure his ankle would just seize up and he wouldn't be able to bend it at all. Cas wasn't having an easy time of it either. Whatever was written all over the walls was affecting him in a bad way. Dean could see the way he squinted his eyes, not even wanting to look at them. Every time he had to put a hand on the rocks to steady himself he hissed and snatched his hands away like he'd been burned. He was sweating too, which wouldn't have been surprising because it was hotter than a sauna in Hell, except for the fact that it had only started after Dean had begun seeing the sigils scrawled all over the walls. Whatever the magic had been that had fucked Cas up earlier, this was a whole hell of a lot more powerful. It was making Cas sick, weaker, tripping over his own feet with a clumsiness Dean had never seen from Cas before.

Dean tried to keep them moving fast, or at least, as fast as they could go, afraid that Cas couldn't keep going for much longer. He wasn't even going to think about what would happen if they were attacked again, or how in hell Cas planned to get them all out of here.

Not far into the wider cavern they found the first corpses, their pale rotting faces looking back at Dean with hollow-eyed horror.

"Exsanguinated," Cas said.

The wide, split-open slashes across their necks and their wrists made that pretty freaking obvious.

The deeper into the cave they went, the more bodies they found, all of them abandoned haphazardly. There was no order to it that Dean could discern, the bodies apparently just left to rot wherever they fell. It was callous and careless and there was no time for Dean to look for ID on any of them, to let their families know they wouldn't be coming back.

Then, somewhere up ahead Dean heard a faint sound like crying or sobbing, hushed words echoing through the tunnels. He hurried them on. Right now the living were more important.

He moved cautiously, careful not to make too much noise, because even though Cas had assured him the creature wasn't anywhere nearby, Dean hadn't lived this long by being careless. Maybe it was kind of crappy to say it, but Dean wasn't entirely sure he could rely on Cas's mojo at that point either.

Creeping closer, Cas tense at his side, the voices became louder, clearer, until Dean could pick out words and accents and a voice so familiar and so fucking _welcome_ that Dean had to stop and just listen. He had to be sure, and that could be no one but Sam.

It didn't surprise Dean that Sam was trying to keep whoever else was with him calm. "Help is coming," he told them. "Yeah, I'm sure," he insisted at their disbelief. From what Dean could make out there were three others, two men and a woman and all of them getting towards hysterical. If they'd seen the corpses and the monster then Dean couldn't really blame them.

It was damn hard for Dean to stop himself calling out to his brother. There were too many unknowns and too much uncertainty.

"Come on," Dean whispered, taking Cas's arm and steadying him in a way he probably should have done a mile back. Cas let himself be led without protest or comment. Maybe too tired, maybe knowing he needed the help but Cas leaned heavily against Dean's side, unstable and breathing hard and Dean frowned. "Can you do this?"

Dean got a pissed look in return for his trouble.

"Of course I can," Cas snapped, but didn't shake off Dean's arm.

"I just thought, you know," Dean offered, "you could hang out here and I'll get the others, then we can head back." It hit Dean then, "Shit. There're are least three other people down there." That made five and Dean had never seen Cas transport that many people even when he was at full strength. Who knew what carrying that many people would do to him in this state, or if it was even possible. "Can you take them all?" Dean asked.

"Yes," Cas said simply, and when Dean raised an eyebrow at him dubiously he added sharply, "I have done more in a worse condition than this."

Not exactly the kind of assurance Dean had been looking for but it wasn't like there were many other choices than to trust that Cas knew his limitations, unlikely as that was. Dean did trust that Cas wouldn't do anything to put him and Sam deliberately in danger. It would probably be best to keep Cas in sight in case he had another meltdown anyway.

"I get it," Dean conceded. They pressed on.

They hadn't gone far when the cavern dipped abruptly down, widening out further. Rock formations curved over their heads creating archways and uneven paths that split off leading to dead ends. They wove their way around obstacles, under low-hanging, sharp stone, through narrow tunnels. It would be easy to get lost in here, stuck in this maze of stone. Dean wouldn't have been convinced they could even get to where the others were this way except Cas seemed to know where they were going, not once hesitating when the path they were following diverged. They passed more corpses, some little more than bones, others newly dead enough that Dean had to cover his mouth with his arm and try not to breathe too much. They didn't stop. There was no point.

The deeper they went the thicker the sigils became until the walls looked almost like they were painted black. There was old, thick blood underlying the more recent half-dried symbols. Dean could smell the metallic tang of it.

Someone, Dean thought, had to have done this. Someone with hands and a knife who was definitely not the giant slug creature they'd been fighting however long ago. It felt like it had to have been hours since they left the woods. It felt like they'd been crawling around in these stifling, foul tunnels for freaking _days_. His watch had stopped somewhere between leaving the motel and now, the face smashed, so there was no way of knowing for sure, not that it mattered much. The weariness behind Dean's eyes told him it was late into the night, maybe even early morning by now, and who knew how long it would be before the monster thing showed up again?

Finally, they came to a slope that they clambered down together, Dean holding onto Cas and the wall so Cas wouldn't have to touch the stone, and Cas in turn anchoring Dean by counter-balancing his weight. At the bottom, the slope opened out into the biggest cavern yet, this one without the maze of tunnels and formations, so wide that the sound of the gravel and stones crunching under their feet echoed loudly. The cavern extended too far for Dean to see where it ended, turning to dark, fathomless shadows even with his strange angel vision.

A few feet away to his right there was a wide niche in the cave wall where it curved around. Along the wall Dean could make out hands, faces, knees, all jutting out of at odd angles from the rock face itself.

Blinking several times to make sure it was real, waiting for his brain to try and work out exactly what his eyes were seeing, Dean couldn't stop himself from saying, "What the fuck?"

Sam's eyes looked up instantly, telling the others to be quiet; two men and a woman, all wide-eyed with terror. They obeyed instantly.

"Sam," Dean greeted and went over to his brother, Cas in tow, to prod at the stone around him. It felt as cold and hard as any other rock.

"Dean, is that you? Oh thank god." Dean grinned at him, but Sam's eyes were unfocused, looking away, and it was then that Dean remembered it had to have been pitch black in the cave and there was no way he could see.

Apart from the fact that he was stuck in a rock face, Sam looked unharmed and Dean was just really damn glad they'd made it before his brother ended up as another one of those abandoned rotting corpses. He sounded smug when he said, "I told you my brother would come."

Even so, Dean couldn't resist. "This is a new look for you, Sam."

"Yeah." Dean watched as Sam rolled his eyes. "This season it's all about the rock-face look. Hey, how can you see?"

"I've got angel eyes," Dean explained.

Sam snorted. "Sure you do. Cas has gotta be with you then."

"I'm here, Sam," Cas said.

"Hey Cas," he greeted warmly, and how come Sam wasn't that nice to him? "I really hope you know how to get us out of this wall."

"How can anyone get us out of here without a jack-hammer and a couple of days to spare?" one of the trapped guys demanded to know. Dean didn't know how long he'd been there but he was white as a sheet, his eyes hollowed out and crazed, making it impossible to tell how old he was. He had one leg free which meant Dean could see he was wearing the kind of ugly red shorts you'd only ever see a tourist subjecting the world to. "Fuck, that thing'll come back before then and kill us all."

"That's not helping, man," Sam tried, soothingly. "Cas?" he asked.

"It can be done. But," he looked to Dean. "I will have to touch the wall."

The sigils were at the thickest Dean had seen here, the paint still so wet it dripped down the wall. Despite the heat, Dean felt a chill at the base of his spine and tried not to think about whose blood this had been.

Dean had to know. "What will that do to you?"

"The same as before, most likely. But more intense. The sigils here are fresh."

"What are they for?" Dean asked. "I mean, what is the point of all this?"

The same guy who'd bitched at Sam before cried out, "The point? Who cares what the fucking point is? Just get us the hell out of here!"

"I care," Dean snapped, "So shut the fuck up or so help me I will leave you in that rock to rot."

There was a tense silence and Dean would've let it drag on just to make the guy squirm but he had no patience and no time for fucking around. "Cas?" he prompted.

Beside him, Cas was trying to straighten up, trying not to lean on Dean heavily. He wasn't having a whole lot of success.

"The majority are summoning sigils. They wish disaster on the inhabitants of this city. There are also spells to ward off prying eyes. Protections. Some are familiar but..." Cas stopped, looking to the ceiling and then down at the floor.

"You don't remember," Dean guessed. Cas nodded.

"Okay. We get them out, we get out of here, we work it out later," Dean decided. Later, when Sam wasn't half entombed in a wall and Cas wasn't looking like he was about to fall over.

But he'd failed to take into account the fact that this was Dean Winchester's life, and no, nothing could ever be that easy.

Cas shook his head. "When I release them the creature that guards the sacrifices will know what I have done."

The woman this time, her eyes swollen and red, sobbed, "Please. Can you get us out of here? _Please_." She was young, not bad looking, and there was blood in her hair.

Dean felt for her, he really did, but he had to be ready if they were going to get attacked as soon as Cas let them out. He left her to Sam's explanations and platitudes, turning his head towards Cas. They couldn't get much closer if they tried what with all the leaning on each other, but maybe that was a good thing with hysterical civilians listening in. In a low voice he admitted to Cas, "We can't move quickly, not with my ankle and you doing an awesome impression of Mr. Floppy."

"Nor can they see," Cas pointed out.

"Shit." Who said things couldn't get any worse? Dean thought for a moment, taking in the open cavern around them; indefensible. It was a long way back the way they'd come but Dean couldn't see any other non-suicidal options. "If we can get them back to the tunnels then no way that oversized bastard can follow."

Cas gave him a strange, pained look. "I don't believe it is the _Asag_ that will be called."

Dean stared at Cas, not getting what he was trying to say, but then he remembered. You needed opposable thumbs to slit someone's throat so neatly. You needed hands that didn't end in claws longer than Dean's arm to paint careful sigils onto walls. "A demon?"

Cas shook his head slowly, and Dean said carefully, "Angel?"

"There is Enochian among these sigils but they weren't painted by angels."

"Fuck," Dean swore. Only one other likely category left then. "A human did this?"

After all the crap he'd seen he really shouldn't have been so surprised.

"It is likely," Cas said.

A human. At least that was something he could kill easily.

"He may have protections around him," Cas went on. "Use my sword."

There was a time, a long time ago, when Dean would have thought twice about killing a human. With everything he's learned and everything he's seen Dean's come to the conclusion that there are some people who are just as bad as any of the supernatural shit they fight. Or worse, because humans were supposed to be better than that. It wouldn't be a difficult thing to put whoever this guy was down.

"If we end him," Dean asked, "Then this'll be over?"

He didn't miss the way Cas fidgeted, uncomfortable. "I can't imagine a human knowing all of this of their own accord." Cas lifted his arm, pointing towards the walls around them. "Some of these spells I have not seen in centuries, others I have never seen on Earth before." He paused, frowning. "That I can remember."

"He's got accomplices then," Dean nodded. Probably made a deal or some shit. Begged for wealth or power, or maybe the life of a loved one because if anyone knew exactly how far a human would go for family or friends it was Dean. "We'll ask him." There was a cold part of Dean's mind that looked forward to the prospect.

"Dean," Cas said warningly. "There is no need for interrogation. I will take the knowledge we require."

Dean hadn't known Cas could even do that, but it had to be better than all the things that had been going through Dean's head; all the ways he could make someone tell him anything. He felt vaguely ill that his first thought had been _torture_. He hadn't even considered that it was fucked up and wrong. Somewhere, Dean had always known that Hell had never really left him, but it wasn't often he was reminded of it so obviously.

"Yeah," Dean agreed, and knew that Cas was staring at him. Maybe he understood, maybe he got it, but he said nothing and Dean was glad for that.

"Help me over to the wall," he said instead, and Dean obliged.

"Oh god, _finally_ ," the annoying guy in shorts bitched dramatically, and too loudly. The woman, patience for assurances gone, hissed "Hurry up." Up until then the third guy, a youngish, shy-looking kid, had remained withdrawn and silently but now he begged, "Please get us out."

Ignoring them, Sam asked, "Is Cas okay?"

"He'll be fine once we get him out of here." Dean kept a hold on Cas's arm as he stepped forward, pressing his palm flat against the stone.

Dean could feel the change in the air as soon as Cas's hand touched the stone. Heat became cold, like ice water poured down his back, and there was light, blinding Dean all over again.

Next to him, Cas was speaking under his breath, a long stream of syllables that Dean had learned to recognise as Enochian.

The civilians were crying for it to stop; that it was too hot, too cold, _too much_. Dean didn't think Cas even heard them.

Trying to blink the brightness from his eyes, squinting, Dean divided his attention between Cas, the exertion showing on his face but determined, and Sam, straining at the rock that held him. He was definitely moving more freely, but was gritting his teeth in pain. It can't have been the worst Sam had ever felt, or even close, because he remained more or less silent.

The light grew, the cold, an impossibly claustrophobic sensation in a cave big enough to hold a house or three. It was like there was something else filling the air, pressing down on them, oppressive. Cas's voice rose, louder, above the cries of the trapped civilians. There was no trace of the same madness and confusion from when Cas had touched the wall earlier. This was confident and strong and fucking powerful. Like this, eyes filled with brilliance and voice resounding with command Cas looked almost frightening. It was so easy to forget, half the time, exactly what he was and what he could do.

He intoned words without stopping once to take a breath, never faltering and it made Dean wonder just how much Cas _knew_. Then, there was a loud crack, like rock splitting. For a second Dean thought it was a cave-in as that bright light filled the room and a gust of wind whipped past his face. The sigils on the walls burned reds and blacks, twining around each other as though they were moving. But suddenly the sound cut off, and when Dean could see and hear again there was Sam and the others on hands and knees, lying on the ground in front of him, panting and shaking but free.

Cas took a deep breath, and Dean waited, torn between going to check on Sam and making sure Cas was sane. He didn't speak but when he looked at Dean there was recognition.

"You good?" Dean needed to be sure.

It took Cas a long moment to reply, and when he did he didn't sound sure. "I believe so." Dean looked to his brother. "Sam?" he asked.

"Great, yeah." Sam nodded and then started levering himself up to standing.

"They will come," Cas warned. "You can let go of me."

Dean wasn't convinced he could without Cas toppling over but he didn't have much choice. Releasing him slowly to make sure he kept his balance, Dean was relieved when Cas actually managed to stay upright.

They stood in front of Sam and the civilians, and even if it was just a human who would be coming for them, Dean pulled Castiel's sword from where he'd stashed it in his belt. He wasn't taking any chances, not when it was Sam and Cas he was protecting.

Dean waited.

 ****

4.

The spirit possessing the priest called itself- _himself_ \- Castiel.

Enlil's pleas to just hear him out, to explain exactly what he meant by _end of the world_ , came to fuck all and Enki wasn't surprised. It was obvious this thing held its orders above everything, human lives included, and Enki didn't believe that was something they could change.

"Three days," Enlil begged. "Give us three days to show you that humans deserve to be saved."

The look Castiel gave Enlil was pitying and grated on Enki's already sorely tested nerves.

"It is not for me to decide," he said flatly. But then the supposed-guardian Castiel looked down and to the side as though he was thinking before adding, "I'm sorry."

If there was one thing Enki hadn't been expecting it was that.

"You would help us?" Enlil asked hopefully, taking the apology as an opening. "If you could?"

A long silence and then, dismissively, Castiel said, "You ask irrelevant questions."

Enki couldn't take any more. "Irrelevant," he spat. " _Irrelevant_. I'll tell you what's fucking irrelevant." He stepped forward and grabbed hold of Castiel's arm. No, not his arm. What had recently been a young priest's arm and had now been stolen by a powerful spirit. Enki didn't care that the thing could probably smite his ass with little more than a thought, or that the other priests were shouting at him in horror, begging him to let the _divine being_ go. If he couldn't kill this thing that was destroying his world, if he couldn't convince it to stop, they were all dead anyway. The possessed body was unnaturally hard and unyielding under his hands and it was likely more the surprise than anything that allowed Enki to pull Castiel outside onto the steps of the temple.

By Enki's reckoning it was the middle of the day, but outside the world was a miserable shadowed place, the sky turned to dull grey by thick clouds. The rain fell so hard it stung Enki's face. Almost immediately they were soaked through. Enki felt himself shivering where a strong, cold wind swept over them. It was winter when the storms came. In the distance he thought he could hear thunder. _The anger of the gods_ , some people called it, and it annoyed Enki that maybe they'd been right.

"This," he told Castiel, waving a hand toward the houses huddled around the temple walls, sprawling outwards across the plane towards the river beyond. By now Enki knew it would be flooded. "This isn't irrelevant. Their lives aren't irrelevant. They mean something. The hell kind of right do you have to take that? You tell us you're not a demon, but that's what demons do. They take the lives of innocent people who haven't done anything more than tried to live-"

"Demons take pleasure in suffering. I don't take pleasure any of this," Castiel interrupted.

"But you don't care," Enki shook his head angrily, gripping _Castiel's_ arm more tightly. As if that would ever actually hurt him. "Or you wouldn't be damn well doing this."

"I wouldn't be able to stop it now even if I tried." Castiel spoke slowly, as though Dean were a child. "You have curtailed my strength like this."

Enki snorted. "Was that some back-handed way of trying to get us to release you? 'Cause I gotta tell you, you're not convincing me."

At some point Enlil had come to stand the other side of Castiel, watching them both carefully, and it was good to know that Enlil had his back. His brother's long, stupid hair had plastered itself to his face.

"We really don't know how to undo the spell," Enlil tried. "Give us three days and we'll find a way to free you from the binding magic-"

"Enlil-" Enki warned, because if they were all going to die he was finding a way to take this thing with them. Enlil shot him a quelling look.

"-without trying to kill us. We kill demons. You hate them too, right? Whatever you've done has brought them all to the party-"

"I called no demons," Castiel interrupted again, and Enki had to admit he really did look genuinely pissed at the news of demons on the loose, frowning every time they were mentioned.

"Maybe you didn't," Enlil conceded. "But they came anyway. You don't have to believe us. We can show you."

Castiel looked to the ground under his feet where the stone steps ran with rainwater. He lifted his head to look out over the city. The rain made it difficult to see clearly but Dean doubted a spirit with Castiel's power would have any problem with that. He could just about make out people gathered at the gates to the city, at the doors to the temple, begging for sanctuary. There was panic, people running frantically about the maze of narrow city streets, though where the hell they thought they were running to Enki had no clue. He heard cries of despair and fear over the rain and the almost-thunder and Enki watched Castiel's eyes. Too old and too intense for any young priest, he took in the homes and the people and the temples and the granaries around them with a blank expression on his too-young face. It was impossible to tell what he was thinking; if he would agree, if he gave a fuck about anything him they'd said or if he'd just kill them and be done with it. From the way Castiel shifted uncomfortably, like he was somehow restrained, Enki was sure he would care about getting out of the binding spell though. He was pretty eager to be out of it himself.

From the very beginning Enki had said this was a bad idea. From the scholars all the way back in Nippur what felt like a thousand years ago, to Enlil in the minutes before they'd performed the binding spell, to Enki magic was good for nothing. They had said it was written in their rituals and their omens that this was the only way to stop the rains and Enki believed it even less now than he had done before. No one had even been able to tell him what exactly this binding spell would do, what its limits were.

It was done now though, and he guessed he'd just have to deal with it.

Castiel remained silent for a long time, staring out over Eridu, before finally saying, "There are many demons here," as though that was news.

"Yeah." Enki thought of their journey from Nippur to Eridu and all the things they'd seen. "And _Rabisu_ , and _Udug_ , and _Edimmu_. The bastards were out in the daytime like it was nothing and they do whatever the hell they like. You really know how to fuck things up."

Castiel turned his creepy, intense eyes on Enki again, staring at him less with anger than with curiosity, like he was trying to work something out.

"It is an unexpected outcome," he admitted. Castiel was doing the not-blinking thing again but Enki refused look away. There was something hypnotic about his eyes and Enki wondered if it was a magic trick, or maybe this was some kind of challenge, some test of his will.

"Come with us," Enlil offered, and Enki could see his brother fidgeting awkwardly out the corner of his eye. "We'll find a way to release you. You have our word on it."

The greater part of Enki's instincts told him this was a waste of time, that they had more chance stopping this by doing what they always did; killing demons and anything else that got in their way, following the case. But something about the way Castiel had spoken, the way Castiel stared at him, made him wonder if maybe they couldn't convince him after all. Castiel made no agreement, gave no indication that he was any happier with being bound to Enki than he had been back inside the temple, but when Enlil turned away to make his way down the temple steps Castiel followed without hesitation. Enki had long since forgone any skins to try and keep himself dry and now he felt the rain running down his back, over his bare feet. None of it bothered Castiel, the young priest's robes long since soaked through, clinging in ways any human would find uncomfortable.

Away from the temple with its cloying smells and humble, reverent priests, Castiel's anger and indignation fell away replaced by curiosity and a whole lot of confusion. It was like he'd never seen _anything_ before; he looked up at the sky and let the rain fall into his eyes and he watched the people hurrying by on the street with interest. And always with the staring. If he'd been in the body of anyone other than a priest, Enki thought, he'd have gotten his ass kicked for the way he looked at people. It was freaky.

"They're all gonna die, you know," Enki said unkindly. He was possibly exaggerating, but down here in the narrow streets of the city the effects of the constant, heavy rain were more visceral. They passed houses with roofs caved in, the roadways turned to shallow rivers, flooding everything at ground level. There was panic and disorder everywhere. The temples weren't helping, closing their doors and calling it the end of the world, and a lot of people believed them and sat in their homes, hopeless and waiting to die.

How could he explain all this to a creature who didn't feel the cold, who didn't smile? If the myths were to be believed he didn't need to eat or rest. From the way Castiel watched the world around him it was obvious he had no concept of what life was like on Earth. How could they make him understand it meant something? Castiel came from Heaven, he said, and from what Enki had been taught of the place there was no pain there.

"Enki," Enlil said warningly. Enki was pretty sure he needn't have bothered because Castiel seemed wholly unconcerned.

"Then they will be at peace," Castiel said. "They will be freed from their suffering."

It was the same religious crap Enki had heard all his life. It was everything Enki had always hated; the obsession with some fairy tale future as though the here and now wasn't important. Enki was the last man who would deny that this life was shit sometimes. He knew better than most that it was hard and there was never enough and half the time it felt like there was always something out to get you. But there were good things too. As far as Enki believed, it was the only life you got.

"You know that for sure, do you?" Enki asked. As sure as Castiel sounded his words had that same brain-washed tone as any other religious fanatic, like this was a line he'd been fed so many times he'd started to believe it, not that he'd actually seen it for himself.

Predictably, Castiel replied, "I know it, yes."

The way Castiel stared right back at Enki, his face blank, made Enki think that even if Castiel knew that all of humanity was doomed to suffer for eternity in the Underworld it wouldn't make much difference to the bastard one way or the other. Enki turned away in disgust, trying to figure out how dragging this creature along with them was going to help anything.

The roads were churned up to not much more than rivers of mud, the skin up to their knees covered in streaks of yellow and brown and Enki hunched his shoulders forward against the chill in the air. Castiel walked steadily, untroubled by any of it looking down curiously at his feet and watching as his toes slid through the mud. There was no point wearing sandals or boots in this, and Enki and Enlil had given up on them days ago.

Closer, louder now, thunder clapped above them. A sign that things were only going to get worse.

To make his life just that little more miserable, Enki wasn't sure how much more he could take either. He hadn't said anything to Enlil because they had enough to deal with as it was, but he hadn't felt right since the _Rabisu_ had bitten him. As they'd walked the roads to Eridu, as Enlil had drilled him in the spells he needed to speak for the ritual, and through the ritual itself, Enki had felt chilled when he should have been hot, sweating in the cold, and his shoulder _ached_. It had been such a damned long day, and there was something draining about having some supernatural creature continuously close by who most of the time Enki would soon as kill as trust. Enki wanted nothing more than to sleep, or at least sit down and rest, just for a while, but no way was he showing any signs of weakness in front of Castiel. Or Enlil, either.

Every step felt too heavy, the world too loud, and Enki didn't know how much longer he could keep up the pace. He only knew that he had to.

***

They didn't even make it to the city gates before they came across demons.

Enki had been pretty sure they wouldn't, and from the almost satisfied look on Enlil's face Enki knew his brother hadn't either. What he hoped to prove to Castiel by being forced to fight demons Enki didn't know. Maybe he meant to test the truth of Castiel's insistence that he hated demons. One of the first things Enki had learned about supernatural creatures was that they lied. It would be useful, too, to see exactly what this Castiel could- and would- do. But there hadn't been any opportunity to talk to Enlil without the spirit close by since they'd left the temple. If this bond thing worked the way the priests had said it did then they wouldn't be getting away from Castiel any time soon. It was not an encouraging thought.

There were five of them; demons with black eyes and ugly, cruel smiles carving up a neighbourhood one family at a time.

Before the rains this would never have happened. No demon would have dared come to a city as rich with protections and priests as Eridu, and yet here they were in broad daylight doing whatever they damn well pleased with nothing to stop them. Enki felt anger and hatred of Castiel burn in his stomach.

There was screaming. People running frantically, slipping in the muddy streets as they tried to get away. Seeing hunters, recognising them from their clothes and their tattoos, the terrified residents grasped at their arms, begging, "Save us! Save us!" Telling them, "They killed my sons!" and "They killed everyone!"

It wasn't hard to make the decision to take these things out, Castiel's help or no.

Keeping their hands on their weapons, Enki and Enlil followed the trail of dead, dismembered bodies lying in the dirt, bright red blood spilling out across the wet, churned-up ground.

Enki watched as Castiel frowned down at the corpses with an expression he couldn't decipher. If he felt any kind of regret or sadness at these deaths he certainly wasn't showing it.

"You gonna help us?" Enki asked. There was no way he was going to trust Castiel to watch his back, but Enki remembered how crazed and how unnaturally powerful the _Rabisu_ had been. He wasn't proud enough- or suicidal enough- to refuse any help he could get.

Castiel nodded. "Yes."

It wasn't much but there was a certainty, a cool determination in his voice that convinced Enki he was telling the truth, and maybe even that he relished the opportunity of killing demons. That, at least, was consistent with what Enki had heard in the stories about guardian spirits; they were warriors who gloried in the blood of evil. Maybe somewhere along the line there'd been a mix up and humans had ended up being classed as the evil ones in need of smiting.

For all the crap humans did Enki wouldn't believe they deserved that. For all the bad there were innocent people, good people, kids, and demons didn't discriminate, murdering young and old and everything in between.

Enlil squatted down next to the body of what had once been a woman. Her long, black hair covered her face, clinging wetly to her shoulders and playing out around her in the mud. One of her arms was missing, torn off at the elbow, and her legs were snapped and broken, lying at sickening angles. Blood still seeped from open wounds along her head, her sides, from where her arm had been. Unhappily, Enlil pressed his hand against the pale skin at her neck.

"Still warm," he said, and stood up, drawing his knife.

Enki did the same, feeling the welcome weight of its handle in his hand.

As much as Enki wouldn't cry over Castiel's death, he wasn't so much of a bastard to let anyone go into a fight with demons unarmed, and Castiel had only the body of a priest to work with. The mess around them told Enki they were dealing with at least three demons, ruthless and strong, and they needed all the help they could get.

"You need a knife?" Enki offered. Maybe he was crazy to give something he didn't trust a weapon that could easily be used to stab him in the back, but there was the binding spell, and there was the fact that Castiel could probably snap him in half with his bare hands if he wanted to. Enki didn't believe he would, though.

Castiel shook his head slowly, meeting Enki's eyes. "I have no need of human weapons."

Enki shrugged. "Suit yourself." See if he cared if the demons ripped him apart. Except, yeah, he did care. Because it wasn’t _Castiel's_ body that would be getting ripped apart. He didn't even know if spirits even could be killed like this, but it would sure as hell kill the priest.

Turning his attention away from Castiel, up ahead Enki could hear the delighted cries of what had to be the demons. There was a sickening tearing sound that Enki didn't want to think about and the screams of a victim cut short.

Enki moved to his brother's side as they made their way cautiously forward. "No time to come up with a plan on this one." Enki spoke under his breath, sure that somehow Castiel could still hear him.

Enlil nodded. "How many d'you think?"

"More than-"

"Five," Castiel announced. "There are five demons."

Enki hissed at him to keep it down, but Castiel just levelled him with an unimpressed stare in return. He glanced at Enki who shrugged. "If there are five of them, we can handle that."

They had no reason to trust Castiel, but Enki also didn't believe he was lying.

"Okay," he agreed, then leaning in close to Enlil he asked, "You think he's invincible?"

"Who knows." Enlil lifted his knife. "Guess we'll find out?"

They'd come to a sharp bend in the street, a corner beyond which Enki was sure they'd find the demons. He came to a stop, pressed his back against the mud-brick of the closest house, listening, trying to decide the best move to make next. The white paint of the walls was slowly being washed away by the rain, creating puddles that looked like milk around the buildings. Nothing was built to withstand this kind of rain and he wondered if the houses would be washed away soon too. Enlil stopped beside him, checking his skin of holy water. Most of their salt had long since dissolved.

Except, Castiel didn't stop. He just kept on walking, right around the corner and out into the middle of the road.

"Hey," Enki hissed after him, reaching out to grab his arm. " _Castiel_."

The bastard moved too fast, not even bothering to look at him.

"Shit," Enki swore.

He heard the demons call, "Hey, pretty!" They whistled and laughed and it made Enki sick. Waiting and trying for surprise was pretty damn useless now.

Swearing again and cursing the damn spirit creature idiot bastard Enki followed Castiel out into the street. He was greeted with taunts and one of the demon assholes shouting," Oh, there're more of them hiding!"

Hiding, his ass. Enki hadn't hidden from one single supernatural bastard in his life.

Their eyes were the slick, liquid black of every demon Enki had ever seen. One of them was chewing on an arm.

This kind of thing Enki had never gotten used to and he felt bile rising in his throat. No one had been left alive. Enki counted seven bodies, part dismembered and disembowelled, the surface of the entire street a pale red where the blood mixed with rain. There was blood on the walls, women, men children, and Enki had to look away. Concentrate on the demons. Make sure they paid for this, and never hurt anyone else ever again.

Something told Enki there were survivors hiding out in the houses around them, watching them. This was a heavily populated part of town filled with poor labourers and traders and their families. He wouldn't let anyone else die here.

"Leave, Hell creatures," Castiel commanded, and there was disgust and hatred in his voice. The vehemence of it surprised Enki.

"Or what?" one of the demons laughed.

Castiel didn't bother replying, just walked towards them, unfazed by the way they taunted and spat at him and told him what they were going to do to him. As far as Enki could tell Castiel was still unarmed. He wondered if, somehow, they'd ended up with the suicidal guardian spirit. Or else he really was invincible. That wasn't what the stories said though. Instead, the tales were filled with spirits who gave everything to save the lives of humans, shredded by demons for a thousand years in vengeance.

A demon in the body of a tall man, his mouth and teeth stained red, moved forward to meet Castiel. He carried a short flint knife, held it up at stomach level. "I'll enjoy cutting you up," he grinned.

Suddenly, another of the other demons stood up from where he'd been hunched on the ground. Enki didn't know what he'd seen or how he'd been able to tell that Castiel wasn't what he seemed, but he called out, "Wait-"

Too late.

The tall demon was within reach of Castiel and before he even had a chance to move Castiel had stretched out his hand and pressed his palm to the demon's forehead. The reaction was instantaneous. At the first touch the demon began screaming, its eyes and its mouth filling with a white, burning light.

"It's a fucking _angel_ ," a third demon cried. He sounded freaked out, looked behind him like he was considering running away. Another drew out a blunt-looking knife and charged at Castiel with inhuman speed, sinking the blade deep into his back.

"Fuck." Enki ran forward, cursing himself for standing around and watching the fight when he should have been putting the demons down himself. "Asshole at the back," Enki called to Enlil in warning, because that demon was looking more and more ready to run and Enki was not letting any of these fuckers get out of this alive.

Enlil nodded, veered away from him, sprinting around the group. Enki trusted him to deal with it.

Before Enki could get to the demon that had stabbed Castiel in the back, he watched as the guy spun around, grasped hold of the demon's neck and threw him clear across the street. The sound of a neck snapping as he hit the wall of once of the houses was unmistakable. That wouldn't keep the demon down for long, Enki knew, but Castiel strode over to the fallen demon and performed the shortest exorcism he'd had ever seen; four words in a language Enki had never heard before and then black smoke was pouring out of the demon's borrowed body and the man fell heavily to the ground. Dead. His eyes open and unseeing. It was probably a kinder end. To wake up after having been possessed by a demon who had murdered and raped and tortured was not something Enki was sure he'd be able to bear. No matter how much they weren't to blame, Enki had seen too many times how those who had been possessed could never live for long with what their bodies had done.

The remaining two demons close by launched at Castiel at the same time. With no weapons of their own they took to fists, getting a painful sounding hit in to his stomach and to his head. Castiel staggered sideways but didn't fall, responded with his own fists, sending the demon he'd punched reeling backwards. The other was going for the knife still embedded in Castiel's back. Enki got to him first, pulling him back by the hair and slitting his throat, all the time speaking an exorcism, running through the words quickly until he saw smoke pouring from the possessed man's mouth and nose.

He'd long ago learned not to think of the humans he killed this way.

When Enki looked back, Enlil had killed their cowardly demon, and Castiel had done whatever it was he did to exorcise the other, the empty corpse falling heavily into the mud.

As fights for them went it hadn't been a hard one, but still Enki found that he was breathing heavily, his shoulders aching, the bite under its bandages itched, stung like fire across his skin. At least during the hunt he hadn't been able to feel it, but now the demons were pretty much dealt with and Enki was reminded that he really wasn't up to this.

From across the street Enlil was giving him a questioning look. Enki just didn't have the energy to deal with his brother and he waved him off. Enki knew there was no hiding that something was wrong from Enlil now, but he would deal with it later.

Right now, Castiel was moving towards him with a weirdly stiff walk.

"Turn around," Enki said, and was kind of surprised when Castiel complied. Enki would never have turned his back so easily to someone- or something- he didn't know.

"You trust me not to slit your throat too?" Enki put a hand on Castiel's shoulder. His skin was warm. At that moment Enki wondered if Castiel even felt pain the same way humans did, but from the way he hissed and arched forward when Enki's hand grasped around the hilt of the sword in his back he guessed he felt _something_.

"Yes," Castiel replied, and didn't make a sound when Enki yanked the blade sharply out of his back. He was bleeding heavily, the red of his blood quickly staining the white robes of the priest.

"You gonna be okay?" Enki asked. It wasn't that he cared but they needed Castiel. Enki could admit that Castiel had been pretty damn badass against the demons too.

"I will heal now," Castiel said, turning back to Enki, searching out his eyes. It was harder this time to stare back. At first Enki thought it was the rain getting in the way, making his vision fuzzy, but then Castiel frowned and Enki could've sworn he saw concern there. Maybe he was going crazy, seeing things. That seemed a whole lot more likely than Castiel giving a crap about him, especially when his whole back and chest felt too heavy, constraining and too hot.

The world had divided and gone dark; there were three Castiels suddenly. Someone was shouting right in his ear and it was so fucking loud it made his head pound.

Then, Castiel's voice, freakily deep and dry, said, "Enki," and Enki forgot he was supposed to be staying conscious in front of the damned creature.

***

When Enki woke it was difficult to remember when he'd gone to sleep. He felt weighted down, lethargic, like he'd done ten rounds with a lion but he couldn't remember fighting anything.

Wherever he was smelled of incense, but without the humid, claustrophobic smell of temples everywhere. More, the air was cool and Enki could feel a breeze against his bare arms. The linen under his back was too rough to be anything found in a temple and Enki was glad for it. It was unusual enough for them to have any sort a bed to spend the night sleeping on, but when they did Enki had always preferred the worn comfort of a home to the expensive, overly-soft temple sheets. Enki hated temples. Too rich, too powerful, selfish places that fed on the superstitions of the poor, and used their supposed importance for political gain. But they were useful, with their libraries and their knowledge, and in his line of work they were impossible to avoid.

It was then that Enki realised someone was watching him. He knew from years of sharing rooms, sharing floor space, sharing blankets, that it wasn't his brother.

"You are awake." There was no forgetting that voice; deep and flat and Enki remembered. It was the end of the world and this was the dick guardian spirit he was bound to. There had been demons and that fucking _Rabisu_ that'd bitten him days ago. He wished he could kill the thing again only this time more slowly, because waking up so slow-minded could only mean he'd passed out, and wasn't that just embarrassing as hell.

"You gotta keep staring even when I'm asleep?" Enki demanded, pissed when his voice came out dry and weak. He felt restless and tired at the same time, and now that he was more aware he could feel something cool pressed against the bite.

Castiel sounded close when he replied, "I have little else to do."

If Enki hadn't known better he'd think Castiel was being funny.

"What, you can't go harass Enlil or something? Where is he?"

Enki still hadn't opened his eyes, not wanting to have to deal with the world just yet. Every part of him felt like shit and he was sure it wasn't going to get better any time soon. He wondered how long he'd been sleeping. It was quiet wherever they were, and dark. Night time maybe.

"I can't go anywhere," Castiel said. "To leave this room, I have found, is beyond the terms of the binding spell." Weirdly, he didn't sound as annoyed about that as Enki might've expected him to. Castiel was speaking quietly, almost softly.

"That sucks," Enki allowed. "Enlil?" he asked again.

"Your brother has gone to find food."

Now he thought about it he was kind of hungry. And thirsty. It was too much to ask, he guessed, to be able to stay in bed for much longer.

Opening his eyes was about as crappy as he'd expected. The only light in the room came from a single oil lamp but it still made his head pound and Enki winced. He was really not looking forward to sitting up. Then, Enki felt dry fingers pressing against his forehead and the pain receded. Not gone, but lessened to a point where Enki could breathe easily. There was only one person who could have done that.

Turning his head, even in the dark shadows of the room Enki could see Castiel sitting on a mat on the floor beside the bed. He was leaning over Enki with a look of concentration on his borrowed face.

"You're not cursing me or something are you?" Enki was suspicious, because he couldn't think of a single reason Castiel would have to help him. He'd never given any indication that he might give a crap about human pain and suffering before.

"I am not." Against all his instincts and everything he'd ever been told about supernatural creatures, Enki found himself believing Castiel. There was no reason after all, Enki guessed, for Castiel to lie.

"What?" Enki asked, "Will you be tied to my bones for all eternity if I die or something?"

From Castiel's touch Enki felt something like soothing coolness, both comforting and creepy. His head cleared, the fire that had radiated out from the bite on his shoulder almost numb.

"I don't know," Castiel said. Enki thought that was all he was going to say, because Castiel didn't seem to be much for conversation, but then he added, "I'm not cruel. I don't seek your suffering."

"But you let it happen anyway." They'd had this conversation already and Enki knew what Castiel's answer would be. But with Castiel leaning so close to him, somehow taking his pain, Enki thought maybe something might have changed. This was a side of Castiel Enki hadn't seen before and would never have expected to even exist.

"I must," Castiel said. "I have no choice."

"Everyone has a choice," Enki argued.

"Humans have choice," Castiel corrected, shaking his head. "My kind do not."

Enki didn't get it but what the fuck did he know about spirits? Whatever, though, because Castiel _had_ made a choice.

"You didn't have to do this," Enki pointed out, taking Castiel's wrist in his hand. It was a relief when the movement didn't cause spikes of pain down Enki's back the way it had since he'd been bitten.

Making eye contact this up-close was a whole new level of weird. Castiel's eyes were a colour Enki had never seen on a human before and Enki wondered if he was actually seeing a part of the _real_ Castiel. For the first time Enki wondered what Castiel looked like. The temple carvings showed beings with the wings of the most powerful of birds, but the great arching shapes Enki had seen back when they'd first summoned Castiel hadn't looked anything like that.

Castiel didn't speak but the way he frowned, studying Enki's face, made him think that maybe he had at least gotten Castiel thinking.

Finally, after so long staring Enki's eyes were getting tired again, Castiel admitted, "I have never been to earth." Enki didn't dare look away because he felt like he might actually be getting somewhere here. There were so many things Enki could show Castiel.

"Do you know what we've done that's so bad your bosses decided we all need to be wiped out?" Enki asked.

"No." Castiel did look away then, tilting his head back to look upwards, towards the Heavens Enki guessed. "Bound like this I can't hear them."

"Would you even ask if you could?"

Without looking away from the ceiling, or whatever it was he was looking at, Castiel said, "No."

Yeah, just as Enki had expected.

It was then that Enlil returned. He stopped dead in the doorway.

"Err- am I interrupting something?" Enki could hear that his asshole brother was trying not to laugh. Enki didn't know what he and Castiel looked like that Enlil found it funny. He was enjoying being pain-free too much to care. Castiel didn’t move at all.

"No," Enki said shortly.

"Right." Enlil coughed, closing the door behind him and coming into the room slowly, cautiously, like one of them was going to snap at him or something. "I got supplies," he said. "Had to beg a few favours. People are hoarding."

He sat on the other side of Enki's bed, and Enki could see that he was carrying a large bundle in his arms, skins hanging off his arm.

"No shortage of water," Enki scoffed.

"No," Enlil agreed, but he was looking at Castiel. He leaned in closer to Enki, whispered, "What's he doing?"

"Looking at the ceiling."

"No, with his-" Enlil put his supplies on the ground and waved at where Castiel still had his fingers pressed against Enki's forehead.

"Oh right. I dunno. Making so I don't feel any pain, or something."

"That's... cool." Enlil gave Enki a significant look.

Enki would've shaken his head but he didn't want to risk dislodging Castiel's touch. "Whatever you're thinking it's not going to work," he told Enlil. Maybe Castiel wasn't as much of an asshole as Enki had thought, but that didn't mean he was going to help them. From what Enki had seen Castiel didn't even really get the concept of making his own decisions, let alone acting on them.

"You don't know that." Enlil, ever the optimist.

Then he looked away towards the door he'd come in through. The apprehension on his face told Enki they had other problems to deal with first. "You think you're good to move?" Enlil asked. And that was not a good sign.

"Trouble?"

"Maybe. I think we've outstayed our welcome."

Enki should’ve known. The world as it was, supernatural assholes everywhere and panic and devastation, there was only so long kindness could last. Before those helping them started to forget how he and his brother had rid them of a bunch of murdering demons and started remembering they were hunters and brought bad luck. It had happened too many times before for Enki to count, and he'd long since stopped getting angry over it. There was some truth to it after all; evil always managed to find them. They were targets for the supernatural more than any civilian.

Still, he didn't think it would've happened so fast.

"How long have I been out?" Enki asked.

Enlil shrugged, glancing towards Castiel. "Two days."

Enlil had asked for three days and here they were two days later and they hadn't even left Eridu. Or at least, Enki assumed they hadn't. The room looked like it belonged to a town house. Either way, it was clear they didn't know any more about how to undo the binding spell now than they had two days ago. Unless Enlil had been checking out the libraries while he was out of it. If their hosts were as unhappy with their presence as Enlil was implying then Enki doubted he'd been able to leave them alone for long. There was no way to predict how Castiel would react to humans.

Thinking of Castiel in this room, Enki realised the poor bastard had been shut inside for two days now with nothing but four walls, a couple pieces of furniture and Enki to look at. The windows were narrow, set too high in the walls to see out of. If it had been Enki he'd have been going stir-crazy by now.

"Castiel brought down your fever," Enlil said.

"Oh. Right. Thanks."

If Castiel had heard him he didn't show it, just kept looking upwards.

Two days. Enki didn't even want to think about how much of a mess the world had become by now. He could still hear the rain outside, the thunder loud overhead.

"Everyone's moving to higher ground," Enlil told him. He'd always been good at knowing what Enki was thinking. "The lower town's completely flooded."

"The river-"

Enlil shook his head. "I don't even want to know how high the water is down there anymore. It's way beyond anything anyone can remember ever seeing before."

"They blaming us yet?" Enki hadn't missed the way Enlil's hand kept straying to the knife at his waist. He wanted out of here.

"Not yet."

Enki knew that look too; nothing direct yet but it wouldn't be long. The worst part of it was that this time they really did have the creature responsible for everything that was happening with them. It was difficult to reconcile something that could destroy the world so callously with the same guy who was keeping the pain from overwhelming him.

"Then we move on." Enki didn't want to have to go anywhere, knowing that as soon as Castiel stopped touching him he was going to feel like shit all over again. But it wasn't like they had much of a choice.

Carefully, Enki started trying to push himself up to sitting. It was a lot more hard work than it should've been, leaving him breathing heavily and light-headed. Enlil was looking at him worriedly, one hand gripping his arm.

"You shouldn't get up," Castiel said sternly. He was holding Enki's shoulder with unexpected care, but still Enki could feel the aching and the pain returning, seeping into his bones and his stomach and down his back. He was grateful at least that he didn't have to deal with it coming back all at once.

"Did you miss the conversation? We gotta go." Enki swung his legs over the side of the bed, let Enlil help him stand. He felt gritty and slow and half-asleep without Castiel's magic and he would have given almost anything to be able to wash. He guessed he'd get his wish as soon as he stepped out the front door into the rain.

"Why?" Castiel asked.

"Because they're gonna think we're the cause of all their misfortune, and you know what? They're not wrong." Castiel was watching him again and Enki glared back.

"You are not healed enough," Castiel insisted, and it was weird that he seemed to actually care about that. "They should show compassion-"

"Like you, you mean?" Enki scoffed. "Like you're showing compassion."

"It's not for me to-"

Along with the pain, Enki's anger was returning. He snapped, "Then you have no right to judge anyone." He turned to Enlil. "We're out of here."

Enki didn't miss the thoughtful look Castiel was giving him, but he refused to return his gaze this time, ignoring him in favour of gathering enough strength to walk on his own. Where they were going, what they were going to do Enki didn't know, but he wouldn't allow himself to believe that the look on Castiel's face was something like understanding. Like he had made a choice.

 ****

5.

More waiting.

Dean had never been patient, and had always found the waiting around, the lulls in between fights, to be the worst part of hunting.

You had to stay alert, because the thing you were trying to kill was always going to try and kill you too. You had to relax or you'd become tired and over-tense and when it came to action you wouldn't be able to move quickly enough. That could only lead to bad things.

The heat and the sprain in his ankle were not helping either.

Dean wasn't sure he believed whatever it was that was coming could really get to them so quickly. It had taken him and Cas at least an hour to navigate their way through the tunnels to reach Sam and the survivors. But Cas insisted it would come, and soon, so Dean stood ready with the civilians huddled behind them. The world was still pitch black for them and that had to be disorienting as hell. It was all Sam could do to stop them from freaking out. Dean could understand why they wanted to run, to just get away. He would've liked more than anything to say fuck it all and have gotten them all the fuck out of there, but they had to stay. They had to find out what the fuck was going on here.

During all that time waiting Dean tried to ignore the way he felt light-headed, how thirsty he was. How soaked through with sweat his t-shirt was, sticking uncomfortably to his chest. He hoped to hell that it turned out it wasn't a human driving Cas crazy, because Dean hated to straight-out kill people. But he would if the fucker was messing with Cas.

He thought he should ask Cas to use his mojo to allow Sam to see in the dark too. It would make Dean feel a whole lot better to know that Sam could defend himself. To know he and Cas had back-up.

There was restless shuffling and scraping behind him and Dean was about to ask what the hell was going on when Sam spoke up, sounding about as frustrated as Dean felt. "Dude, sit down."

The addition of the civilians to this equation made the whole situation all the more fucked up. Three extra lives to think about and how the hell Cas was supposed to carry all of them out of there when he was so down on juice Dean did not know.

"Dude," Sam said again, and Dean was about to yell at whoever it was to do as he was damn well told when there was a shout, a half-crazed laugh that set Dean's nerved on edge. Dean turned just in time to see the quietest of the civilians launching himself at Cas, burying the point of a long, silver knife into his back.

It would be too much like luck for Castiel not to feel it. For him to be able to pull out the knife with the same disinterest he had back in the barn when they'd first met and Dean had assumed he was a demon. This time Dean could see the way Castiel gritted his teeth and hissed in pain as he tried to twist away. Dean cursed himself for not being more careful. He should've suspected. He should've checked the survivors out. But he'd thought they were the victims and there'd been no time. There was nothing he could do about it now except correct his mistake.

His face had been so blank before, but now the guy's face was twisted into an expression of glee and he pulled the knife ruthlessly from Cas's back, holding onto the angel's shoulder in a way that convinced Dean he meant to stab him again. And that was not going to fucking happen.

Dean launched himself at Cas's attacker, aiming for the guy's weapon. He might have a big, shiny knife, but Dean had a bigger, shinier angel sword and a whole lot of rage to work through.

Somewhere to his side he heard Sam shout, "Dean, what the hell is going on?" There was hysterical crying, the crazy guy's high-pitched giggles, but all Dean was listening to was Cas's choked, wet breaths. The asshole had to have driven his knife right into Cas's lungs.

Dean grabbed at the guy's arm, yanking it away with all his strength, twisting the wrist so far around that it forced him back, allowing enough space for Dean to knee him in the stomach. He tried to take a bite out of Dean's neck like he was a fucking vampire so Dean shoved an elbow up into the guy's chin, knowing better than to let go of his opponent’s knife hard. Instead, Dean gripped the wrist more tightly, trying to bend it back and upwards, trying to break it. The move half worked, the guy obviously unused to hand-to-hand fighting because he cried out in pain and attempted to pull away which only made the hold Dean had on him more complete.

The guy was strong though- stronger than any human his size should have been- and it was clear he could see in the dark, meeting Dean's eyes with a manic, wide-eyed stare that creeped Dean out. He kicked out, his boot meeting Dean's knee and agony shot down Dean's leg to his ankle and Jesus Christ at this rate he wouldn't be able to walk for a month when this was over. And he _would_ get out of this, the same way he always had; by beating the evil sons of bitches until they stayed down.

It wasn't even close to the worst he'd ever felt so Dean kept his ground, jammed his knee into the guy's groin, unwilling to use the sword until he had to because they still needed information out of this asshole. Using the handle instead, Dean whipped the guy around the face and was surprised when he suddenly went limp, falling heavily to the ground. His long, silver knife clattered against the stone floor, still streaked red with Cas's blood. There were symbols all along the blade that Dean didn't recognise. Cursed, Dean would bet. The thought of what damage it might've done to Cas made Dean want to beat the guy some more, even if he wasn't moving, so he kicked the knife away angrily. Kneeling down cautiously, Dean tapped at the guy's face to check he wasn't faking. His chest was still moving, still breathing, and Dean reminded himself they needed him alive for information.

There was a deep cut, blood running down the side of his face where Cas's sword had struck him and Dean wondered just how damn solid angel weapons were to do that kind of damage. He didn't remember hitting the guy _that_ hard. But who the hell knew. He deserved what he got. The bastard had tried to kill Cas, and holy fuck _Cas_.

He looked over, saw Cas lying on his side and there was one hell of a lot of blood pouring out of the deep wound in his back. "Cas," he called. Cas's face was turned away, and Dean couldn't even tell if he was even conscious. "Come on. Why aren't you healing?"

No reply.

Not wanting to leave this fucker unguarded, but needing to get to Cas, Dean hesitated. He had nothing to tie the bastard up with and Sam couldn't see.

Back against the cavern wall Sam was busy fighting to hold back one of the other survivors, the woman, who was struggling and sobbing. Dean considered the possibility that she and the third survivor were connected to this too. That they were dangerous, but the woman sounded hysterical, and the other man was sitting, staring blankly ahead of him and it seemed more likely that it was just shock. Panic and confusion. Sam caught his attention then, calling, "Cas. Dean, _tell me what the fuck is going on_." His eyes searched desperately, blindly around him.

"It was the quiet one," Dean said, and Sam subsided with a breath of relief. "He stabbed Cas."

"Shit, man."

"He's not dead, but out for now."

The woman had taken up a litany of, "Oh god, oh god, oh god," over and over again.

Taking one last look at the passed out guy, making his decision, Dean stowed Cas's sword in his belt and stood up.

"Is Cas okay?" Sam asked, and he was starting to sound kind of pissed and frustrated. Dean could get that. It had to suck to not be able to see but to know that bad things were happening right in front of you. "Dean?"

Falling to his knees at Cas's side, wincing as the movement pulled at his messed up ankle, Dean could see that Cas's eyes were closed and he wasn't breathing a whole lot.

"I'm just checking, Sam. Hang on."

Leaning closer to get a look at the wound in Cas's back, Dean did not like the amount of blood already staining the back of Castiel's coat, running down to pool on the ground.

"That bastard stuck him in the back with a knife and it looks like he's bleeding out," he told Sam. All he could think to do was to try and stop the flow, and he grimaced as he pressed his palm down, feeling the stickiness, smelling the copper tang of blood. It was too human.

At the pressure Cas arched away Dean's hold, making a pained sound. No way he wasn't awake now, anyway.

"Cas," he said urgently. "Tell me why you're not healing." Dean hated himself for pressing down harder. "Cas."

Cas coughed wetly, blood on his lips, but he managed to say, "This place. Sigils."

"You gonna die on me?" Dean demanded to know. "Because I've gotta tell you, that's not cool."

It took way too long for Cas to reply. "Not here."

"I'm gonna hold you to that."

Dean looked over to the unconscious guy. He still hadn't moved, and if Dean hadn't needed him he'd have made sure the bastard never moved again. Under his hands Cas shivered despite the heat and Dean hated that he couldn't even let Cas rest.

"D'you know if that guy was the one who did this?" Dean asked, nodding back towards the corpses they'd found.

"The knife," Castiel said, and it took Dean a moment to work out what he meant. Shit. He'd kicked it away and it took several minutes to locate it again. Minutes when he had to move away from Cas, letting him bleed. He was back at Cas's side the instant he'd found the damn thing, held tentatively in his hand in case it really was cursed. Pressing down again against the wound, Castiel stirred.

"Hey," Dean greeted. "I got it." He held the knife up to Cas's eye level.

Cas blinked a few times and Dean thought his eyes looked like they were trying hard to focus. Taking a painful sounding, uneven breath, Cas said, "He killed them, yes."

He tossed the knife away again so he could touch Cas's face, trying to keep his attention.

"Just a couple more questions, Cas," Dean promised. "If that asshole wakes up, can he call the slug monster here?"

"He- possibly. These sigils. These sacrifices-" Cas stopped to breath and Dean stroked a thumb across his cheek lightly.

"You're doing good, Cas," he encouraged.

Cas gave him a weak smile in reply. "It was likely the purpose of the sacrifices to call upon the _Asag_."

That the monster could be controlled was one thing, but that they didn't know if there was some other psycho out there who could set it on them or something was disconcerting. With Cas in this state there was no chance of fighting it and very little chance of him flying them all out of there any time soon.

He must've been listening in because Sam asked, "What are we gonna do?"

Dean had been wondering that too.

He looked over at Cas's attacker again, still lying unmoving. "We're gonna have to leave that bastard behind," Dean decided.

There was no way was he leaving Cas here. Dean didn't think he'd even be able to defend himself against a puppy right about now, let alone some thick-skinned slug monster.

"He's our only lead," Sam pointed out.

"Yeah," Dean said. "I know."

Dean turned to find the path he and Cas had taken to get to Sam; steep and uneven and leading to miles of winding tunnels that Dean wasn't confident he could navigate his way back through again. The other way looked more open and wide, like maybe that was the route the monster took to get down here.

"That guy had to have known a way out," Dean reasoned. "And he didn't come the way we did." It was still an assault course of jagged stone and steps and falls as far as Dean could see.

"That creature could come back at any minute," Sam said, but he was already helping the remaining two civilians to their feet. They'd both fallen quiet.

"Not really much of a choice." Dean shook his head, trying to work out exactly how he was supposed to lead Sam and the survivors and carry Cas all at the same time. They were going to have to go painfully slowly to avoid anyone breaking an ankle, or their neck. That was going to make the monster coming back all the more likely. It had to be getting to dawn by now and as far as Dean could tell the creature didn't come out in the daylight. No one had ever claimed to have seen anything like the thing they'd fought the night before, and Dean doubted something that ugly could be easily forgotten.

"We need to move." At some point Cas had closed his eyes so Dean shook his shoulder gently. "Hey, you good to stand up?"

The look on Castiel's face told him that no, he really wasn't, but he said gamely, "Yes."

Carefully Dean wound his arms around Cas's waist, trying not to let up the pressure against the knife wound. It was awkward and pulled every damn muscle Dean had to get into a position that worked but somehow he managed to lever himself and Castiel into standing. And Jesus, Cas was heavy. Dean didn't think he was taking very much of his own weight at all, but hung mostly limp in Dean's arms, shaking faintly and wheezing like an old man.

"He okay?" Sam asked, because there was no missing that noise or the pained gasps Cas had made as they got to their feet.

"I really don't think so," Dean replied. "I'm gonna need your help carrying him. You think you can find us?"

"Um," Sam said uncertainly. Dean watched as his brother felt his way down the cavern wall to the floor where he shifted awkwardly onto his hands and knees. "You're gonna need to say something so I can find you," Sam said.

"You look ridiculous," Dean told him and smiled despite everything because it was kind of funny to see Sam crawling around, feeling his way blindly across the ground.

"I'd like to see you try this, jerk-face," Sam shot back.

Dean had to admit, Sam was doing a pretty good job of following his voice.

"Hey, I'm just trying to be helpful."

The surviving man called out to them, panicked, "You're not going to leave us here are you? That thing'll kill us. Or that guy. Fuck, I don't know what the hell is going on here."

"No one's getting left behind," Dean assured him, and felt Cas stirring in his arms. "Cas," he said in a quieter voice. "How you holding up?" He tried adjusting his hold, trying to get a look at Cas's face to see if he was all there but they were pressed too closely together. Cas's face was mashed up against his shoulder so all Dean could see was the slant of his nose and his heavy-lidded eyes.

In a muffled slur Castiel replied testily, "I am not," and Dean couldn't work out if he meant he wasn't doing well or if he'd taken Dean literally and was telling him he wasn't, in fact, holding anything.

That Cas had replied at all though was enough, and Dean turned his attention to Sam who had managed to make it almost to where they stood. Against him Cas had started, unhelpfully, squirming in Dean's hold.

"Keep still," he ordered. "I got you, but I won't if you keep doing that."

"I can't seem to stand up," Castiel said, sounding confused like he didn't know _why_ he couldn't stand.

Dean frowned. "You remember what happened, right?"

"I- yes. I remember." The pause worried Dean. For a moment, Dean didn't think Cas _had_ remembered. He was shivering again despite the heat and being pressed right up against Dean, still wearing his heavy trench coat. It should've been uncomfortable- it was uncomfortable, because Cas's skin was burning hot and Dean was sweating like crazy- but it was Cas so he didn't mind so much.

Even if he was damn heavy.

"Over here, Sam. More to your left," Dean called and was relieved when Sam's outstretched fingers bumped against the sole of his shoe. "Yeah, that's me. Now get up here and help me. Cas?" Dean felt like an ass for pushing him this far when Cas tried to take a breath to speak and it caught in his chest. He choked and coughed and Dean could see the blood on his lips again. "Shit. " All he could think to do was to hold Cas more tightly, wishing there was some way he could fix this. He cursed the human who'd done this, _wanting_ to rip the asshole to shreds more than ever for what he'd done to Cas and surprising himself with his own viciousness. "Don't talk any more," Dean tried. "Just nod or shake your head, okay?"

Cas nodded slowly, calming his breathing and gripping at the back of Dean's shirt.

"Cool," Dean encouraged. "I'm sorry, man, but can you give Sam the same night-vision you gave me? I need help getting us all out of here."

After a pause Castiel nodded again.

"Awesome. You're doing awesome. Sam, stop fondling my ankle and get up here."

"Not as easy as it looks, Dean." Sam replied dryly. "I can't even tell which way is up or down. It's disorienting as hell." He used Dean's leg to guide him up and Dean nudged at him with his elbow to indicate where to move to.

"Do it now, Cas," Dean urged. He'd finally gotten Sam standing right in front of them and wanted to get this done quickly. Watching as Cas reached out an unsteady hand towards Sam's eyes, he could see blood and dirt streaking his hands, black stains along the arm of his coat.

Cas shuddered as he pressed his fingertips to Sam's eyelids and Dean could feel him tense, straining. He hoped he hadn't asked too much. Dean always seemed to end up asking too much.

Sam stumbled, blinking rapidly and spreading his arms out like he was trying to keep his balance, and Castiel let his arm fall heavily to his side.

"Woah." Sam brought his hands up to his face, waved them around in front of his eyes. "This is weird."

"Yeah, you can see again," Dean said impatiently. "Now get over here and _help me_."

Dean could see the horrified look on Sam's face when he turned to Cas. "Jesus. Oh shit. Castiel."

Never had Dean been more glad that his brother was a tall freak and damn strong when he hefted Cas upright one hell of a lot more easily than Dean had on his own.

"Careful, man," Dean hissed. Sam was moving Cas too quickly, dislodging the hold he had on the wound in Cas's back. Dean hated the way his hand felt hot and wet and sticky from Cas's blood.

Dean could see Sam rolling his eyes. "It's good. I got him."

"I do not appreciate," Cas said from between them, and even though he sounded weak he still somehow managed to sound pissed as hell, "being handed around like a doll."

"You don't, huh?" Dean snorted. "Then next time don't get stabbed in the back."

"I did not-" Cas began, but it was like he'd run out of steam because Cas stopped arguing and sagged even further, giving up any pretence of holding himself up. Dean would've panicked that he'd gone and died on him or something if he couldn't still feel the movement of Cas's back under his hand as he breathed.

"We're moving," Dean announce and Sam nodded, pulling Cas's arm around his shoulders.

"Okay, you guys," Sam called to the civilians. "We're getting out of here. Hold on to each other’s hands, or shirts, or whatever. I'm gonna come get you and one of you hold onto my shirt. We'll take it slow."

By the time they had their two survivors secured and latched onto Sam, Dean was getting antsy and Cas was starting to murmur in that foreign language he'd used before. Sam had said was some kind of Persian and Dean knew that somehow it was connected to all this.

He got them walking before he'd even really decided on a direction because it would get the civilians concentrating on things other than the creature coming back. If he were honest it helped Dean focus too, and it felt good to be moving away from Cas's attacker. Dean just really fucking hoped the guy wouldn't wake up and come after them.

If it were left to Dean, if Sam and Cas and the other victims weren't there, Dean wasn't entirely sure he wouldn't have killed the fucker.

Leaning in closer to Sam, speaking in a low voice so the others wouldn't hear, Dean asked, "How'd you get in here?"

"I have no idea. I was passed out for that part." They sidestepped a fallen rock, causing Cas to grip Dean's shoulder more tightly, his eyes closed in pain. "Watch your feet," Sam warned, then to Dean, "What about you? Cas got you in, right?"

Dean lifted his chin to towards the back of the cavern. "There're more tunnels back that way. They don't go anywhere. Cas flew us in."

"So we don't know where we're going?"

"We head upwards. Stick to the bigger tunnels. That monster made it down here somehow."

"Unless it didn't," Sam pointed out. "And it was that crazy dude who brought us here."

"Okay," Dean conceded. "But that guy got down here somehow."

It wasn't like they had any other choices.

Dean was just hoping that if they could get Cas away from the thickly laid sigils he'd be able to heal. Where Dean had his palm pressed against Cas's back he could feel fresh blood still oozing from the wound. The poor bastard couldn't have that much blood left in him by now. Cas had promised not to die though, and Dean was holding him to that.

As they moved through the cavern Sam gave directions to the two survivors to take large steps, that the ground took a sharp incline, that there were potholes to go around. It was laborious and they made painfully slow progress. When he could, though, Dean noticed Sam looking around the cavern, his eyes wide.

"Who'd have thought?" Dean said, trying to relieve some of the tension and trying to take Dean's mind off of the agony that shot through his ankle with every step. "All these tunnels under Chicago. Lake Michigan. Wherever we are."

"It's incredible," Sam agreed. "Did Cas say what all these symbols were? This is what's stopping him healing, right? Who drew them all?"

"Some of them are anti-angel symbols, yeah. I dunno who painted them. No way that guy could have done all this."

"There're layers of them. Who knows how old they are."

Dean recognised the wonder in Sam's voice. "Oh no. We are not coming back here so don't even think about it."

Sam didn't argue, which meant that that was exactly what he'd been thinking. It was clear from his all-too innocent frown that Sam wasn't done with this discussion yet, but their path was climbing steeply now and with Cas held between them and the civilians following neither of them had any breath to spare.

Dean didn't like the way Cas was so out of it, not fully awake. He stumbled along but when he lifted his head there was confusion and incomprehension in his eyes. He was just glad Cas never freaked out and tried to pull away. It was like, no matter how far gone Cas was he always recognised him and Sam. That Cas could trust them that much, that they were that far embedded into Cas's subconscious or whatever so that he recognised them even when he didn't was both kind of humbling and frightening at the same time. Half of the time Cas acted like he had better things to do than even talk to them, but to have that kind of proof that despite everything Cas really was still their friend was reassuring. And awesome.

They followed the path of the cavern as it angled even more steeply upwards, becoming narrower but still wide enough to easily fit a car. The sound of their heavy footsteps as they navigated around the uneven ground and their laboured breathing echoed loudly off the walls and the ceiling. The hot air tasted too thin and for a long time the humidity had really been getting to Dean but now it was getting to Cas too because Dean could see sweat on his forehead and running down his face. Not a good sign.

A couple of times Dean would've sworn he smelled fresh air, could feel a breeze across his face, but when he turned towards it, it was always gone. Maybe it was just his imagination. Maybe Dean was going mad too.

They had to keep stopping to readjust their grip on Cas, or because one of the civilians had fallen down or scratched something, or because they all just needed to stop and breathe. It was slowing them down to a crawling pace, and it hurt Dean's ankle more when they stopped and he could actually feel the burn than when they were moving and he could just concentrate on putting one foot in front of the other and not letting go of Cas. And Cas was fading. From the worried looks Sam kept sending him Dean knew his brother could see it too. Sometimes he stopped breathing for whole minutes and Dean had to remind himself for every second of that time not to panic; that Cas didn't actually need to breathe. He'd probably just forgotten or something.

The layers upon layers of sigils and symbols covering the walls weren't getting any less. If anything they were becoming thicker, older, and Dean was starting to think he'd made the wrong decision.

After everything they'd done, to get stuck down here wandering this maze of underground tunnels forever was not fucking cool. Dean refused to become some ghost, haunting this place and spending all eternity looking for a way out.

He tried to ask Cas, "Hey, can you tell which way we should go?" and received a blank look in reply, like Cas hadn't even understood the question.

And then they heard a scream. It was definitely human, male, and coming from somewhere behind them. In these caverns it was impossible to tell how close or far away he might be because of the way sound echoed all around them.

"It's gotta be that asshole," Dean said to Sam in a low voice, and wished he had killed him after all.

Sam was looking over his shoulder. "You took his knife, right?"

It was a simple mistake. Dean hadn't even considered it, too caught up with Cas bleeding all over the place and getting the hell out of there and none of that was any excuse.

"I might've forgotten," Dean admitted.

A crazy guy with a knife that could do damage to an angel was not an added complication any of them needed. Dean was grateful that Sam didn't bitch him out for it. Their dad would have, and Dean would have deserved it. Maybe they were all just too tired. It was inevitable mistakes were going to be made, and whatever, it was done now and they were just going to have to deal with it.

"We need to move faster," Dean said, and no one made any arguments about that. The civilians, clinging to Sam's shirt and to each other, had been silent when they'd heard the scream, and kept quiet now as they moved on. They were listening, Dean guessed. Listening cautiously for any sign that the crazy guy was close behind them in the dark, wielding a knife and ready to stab them all to death. Dean wished he could get Cas to give them night vision too because it would've meant being able to move one hell of a lot faster, but with Cas so out of it he didn't think that was going to happen. Giving sight to Sam seemed to have pretty much taken whatever strength Cas had left out of him.

They didn't stop as the walls drew in closer, different paths veering off from the main cavern. Dean stuck to the largest tunnel desperate not to get any more lost than he already was. Cackling and insane laughter followed them and it put Dean on edge because for all they knew their crazed stalker could've been only feet behind them. Every step was an effort; a painful reminder of the damage his ankle had endured and of how thirsty he was and of how pretty much every muscle was aching, pulled and bent out of shape.

"Dude." Sam was peering at him, concerned. "Are you okay?"

Sam was breathing heavily, taking a lot more of Cas's weight than Dean was, and Dean knew he wasn't exactly at his steadiest, tripping over nothing.

Automatically, Dean replied, "I'm fine."

"Sure you are," Sam snorted. He could scoff in Dean's face all he wanted but none of them could do anything to make this better. They couldn't even stop and rest.

Dean was going to tell Sam he could carry Cas on his own if he was so damn worried, but then there was a long, ear-splitting scream that Dean had become way too familiar with recently.

"You have got to be fucking kidding me," he groaned.

Dean had known that sooner or later this was going to happen, but that didn't make it any easier. It had been easy to think that they had more time, to ignore it, but here was the monster, come home. Dean checked his belt with his free hand, making sure that Cas's sword was still there, that he could get to it if he needed to. The hilt was cold against his palm.

At the first touch of his hand against the sword Cas startled awake, his legs locking up so suddenly he almost overbalanced them all. Dean tried to believe that had been a coincidence.

Hanging there between them Cas blinked furiously, coughing, and Dean wished they could stop and rest.

"Calm down, Cas," Dean tried reassuring him, urging him forward, trying to keep them moving. "Just relax. We got you. I'm getting us all out of here."

"Enki," Cas looked right into Dean's eyes. There was shock there, like Cas couldn't believe he was standing there right in front of him. Like it was the most amazing thing in the world that he was. Cas had called him that name before.

"I'm not him-" Dean said, but Cas shook his head and spoke in that same guttural, foreign language he'd been slipping into all day, since they'd found him on the shores of Lake Michigan. It was weird to think that could only have been a few hours ago instead of the days and days it felt like.

Whatever Cas was saying it sounded urgent, maybe an explanation, but there was regret too. So much regret that Dean was glad he couldn't understand the words.

But Cas speaking in that other language was always followed by him losing it, going just that little bit more crazy, and every time it'd been more difficult to bring Cas back.

"English, Cas." Dean was trying to head if off but had no clue what would work. Touch had stopped him before, being reminded who he was with, but Sam and Dean couldn't _get_ any closer to Cas if they tried.

Dean watched as Cas stopped talking and frowned at him, confused but visibly trying to pull himself together. It wasn't easy to keep looking at Cas and not trip over on the uneven ground but Dean was determined. This was working, somehow holding Cas's attention to the present, and if he could keep Cas with them and alert then maybe he'd be able to guide them out.

There was another howl, another painfully loud screech. It sounded closer but maybe that was just the echoes. Whatever recognition Cas had regained was gone in an instant and he started struggling. Dean might not know the language but he could understand the tone; Cas was _angry_. Bitching him out. And when he was done with Dean he turned to Sam, said, "Enlil," and started giving him exactly the same treatment.

All the movement as Cas tried to pull away and fend them off was making the wound on his back start bleeding again when it hadn't long stopped. Dean could feel the warm wetness under his hand.

He ground out, "Will you fucking stay still," but that just made Cas struggle even more, shoving away from them. Even weakened Cas had one hell of a lot of push in him and he managed to get his arm untwined from Sam, stopping dead and not moving. Unable to see them coming to a stop, the civilians walked straight in to Sam where they'd been following him, holding onto his shit. They yelped and started to panic, demanding to know what the fuck was going on.

Dean would like to have known that too.

Just a little way back there'd been a recess in the cavern wall, like a short dead-ended tunnel. It could hide them for a while and Dean called for Sam to take the others back there. They couldn't keep moving like this. He grabbed Cas's wrists, holding them tightly and trying to get his attention, to get that recognition back even if was for someone Dean wasn't.

The screechy woman demanded, "Why are we going back? We shouldn't go back." He hadn't bothered to ask their names and Dean felt like a tool when he heard Sam trying to explain, "Vanessa, we have to stop. Our friend is- sick."

The man spoke up, sounding angry and indignant, "We have to leave him behind. There's no time for this. We can't stay. We'll be _killed_."

If Dean hadn't had Cas to deal with he'd have ripped the guy's fucking head off.

Sam told him coldly, "We'd still be stuck back in that wall if it wasn't for Cas. You say one more thing about leaving anyone behind and I’ll leave you right where you stand."

He left Sam to deal with the ungrateful dick, concentrating on Cas, but couldn't decide who'd gotten the worst deal when Cas started up blabbering in that foreign language again. He sounded like he was pleading now, breathing heavily, but at least this time there wasn't the wet click of messed up lungs when he talked. Dean guessed Cas was healing after all, if only slowly. Even in the weird colouring of angelic fake night vision Dean could see how messed up Cas looked. His attempts to pull away from Dean were slowing. Cas was wearing himself out.

"Come on, man," Dean pretty much begged. "You know me. I'm Dean. I only understand English. You _know_ that."

Before, Dean had held on to Cas's face to get him to snap out of whatever the hell this was. He hadn't let Cas look away. He'd held his gaze and Cas had come back so Dean tried it again, reaching out and taking Cas's head in his hands. Cas was so damn cold. Everything was the wrong way around in this place.

Another loud howl, louder than before, but Dean ignored it.

"You're a dick and I'm an asshole," Dean tried, hoping he could hear him over the cries echoing around them. "We fight apocalypses with Sam and we win."

Cas tried to pull his head away, and all Dean could understand was Cas repeating that name over and over again; "Enki. Enki. Enki."

Maybe this was someone Cas had known all those six thousand years ago when something had happened that Cas couldn't remember. Maybe this was Cas remembering. Dean couldn't help but wonder who this Enki had been, and what he'd been to Cas that when he said his name it sounded like despair.

Words weren't working though. Dean didn't think Cas could even understand him. He really didn't want to try anything like hitting Cas across the face because Cas was in bad enough shape already. There was only one thing left to try that he could think of and Dean just hoped Sam wasn't looking their way because this was not something he wanted his brother to see. With Cas so out of it and not thinking straight this was the very last situation Dean would've chosen for this but he was out of options and out of time. He just hoped to hell it worked and that Cas didn't just smite him where he stood.

If he thought about it anymore he'd never be able to do it so Dean leaned forward, holding tightly onto Cas, and kissed him with everything he had. They'd never done this before and Dean hoped the shock of it would push Cas into remembering _something_. Mostly, Dean wanted Cas to remember _him_ , and that there had always been this weird frisson between them that made Dean think sometimes that Cas wanted to kiss him as much as Dean wanted to kiss Cas.

For what felt like long minutes Cas didn't respond. He went still, almost rigid, and Dean took advantage of his stillness to move closer, to press against Cas's body. Gently, Dean ran his hand down Cas's back, trying to find the stab wound, to check he wasn't bleeding out. It was hard to concentrate, because maybe Dean had kind of wanted this; to get this close to Cas. But, God, not like this.

Then Cas started kissing him back and all Dean could think was, _I hope he knows who I am_. The thought made Dean stop and pull away, and when he looked into Cas's eyes, Cas was looking right back at him and Dean had his answer. He needed to be sure.

"Tell me who I am," Dean said, one hand still holding Cas's face, the other held lightly against his back. The wound was mostly dry, no new blood.

It was too hot for how close they were pressed together, and they were both such a freaking mess, and there were things baying for their blood out in the dark, but in that moment Dean didn't give a crap about any of it.

"Dean," Cas replied.

 ****

6.

Girsu was the smallest of the southern cities. It stood on the high ground, well above the plains and the river valleys, and Enki and Enlil found themselves crowded on the old, worn paths leading to the city gates alongside hundreds of refugees fleeing the floods and the demons. Still the rain fell and the road had been turned to such a mud bath by the multitudes of feet pounding up the dirt that they had to walk along the edges, now turned to banks as water washed down what had once been the pathway. It was a slow, painful slog, made worse by Enki's still aching shoulder. As they walked Enki could feel eyes staring at them, accusing. For such a great number of people, weary, drenched and dirty, the journey was oddly quiet. Maybe no one had the strength left to even speak anymore.

Most kept their distance from the hunters and even from Castiel, dressed as a priest for all that he wasn't. It might've been down to association with him and Enlil, but Enki thought it more likely they could tell there was something not right about him. Something not human. The rain, the mud, none of it concerned Castiel. He was too strong, too tireless and confident for a priest with thin legs and a youthfulness not matched by his eyes.

Castiel followed, never complaining, never offering any comment on what he saw around them. Somehow he'd been roped in to carrying the supplies, or what was left of them after three days hard walking, while Enlil acted as crutch to Enki. He didn't eat or drink or sleep as far as Enki could tell. It was hard to know for sure because when they stopped for the night, just falling to the side of the road, finding what little shelter they could and covering themselves with skins, Enki found that he fell straight into an exhausted sleep. Castiel hadn't killed them while they were passed out yet so Enki assumed they were more or less safe from that danger. Sometimes Castiel even helped them; keeping Enki steady when the ground was too wet and he slipped with every step. When Enlil was too tired to carry him anymore Castiel would take Enki's weight like it was nothing. Sometimes he helped others around them, pulling fallen old men to their feet, carrying children on his shoulders as they forded rivers that hadn't existed a few days before. None of it made sense.

That night, with maybe one more day to walk until they reached Girsu, Enki managed to stay awake long enough to ask, "Why bother? If you had your way they'd all be dead already, right?"

They were huddled beside the one surviving wall of an old abandoned farm house. It was the most shelter they'd had in days. Enlil was already asleep, leaning against Enki's good shoulder. There were at least three other families close by so Enki kept his voice low. This had once been lion country but Enki hadn't seen a single animal the entire journey, like they’d all had the sense to get the hell out of there before it all went to shit.

There was lightening to the east, intermittent bright flashes in the sky that allowed Enki to see the muddy nightmare around them and Castiel's impassive face. He'd rather not have seen either. The rolling thunder was the only thing that drowned out the soft, exhausted cries of the children among them. It was depressing as hell and Enki couldn't understand how Castiel could sit there and watch all this, knowing he had caused it.

"No," Castiel replied. "They wouldn't." It was almost an opinion.

"You act like a guardian spirit half the time," Enki pressed. "But you caused this."

"I have told you," and now Castiel actually sounded frustrated. Maybe he was getting as tired of this conversation as Enki was. "I cause nothing."

"Yeah, I know, you just follow orders. But, man, look at what you're doing. There's no way you can think this is _right_."

"What I think makes no difference." Castiel sighed and it was the most human sounding thing he'd ever done. "Enki, please. I can no more affect the outcome than you can."

Which was clearly not the truth or he wouldn't have been the one tied to Enki by this spell.

"But you wouldn't do this, if you hadn't been ordered to," Enki surmised.

"Of course not," Castiel snapped in reply. "I'm not-" He stopped, and Enki could feel the muscles of Castiel's borrowed body, tense and agitated beside him.

And to Enki that was pretty much an admission that Castiel didn't believe this was a good thing he was doing either.

On these long nights Enki inevitably lost feeling in his fingers and toes from sitting for so long in the pouring, cold rain. He tried moving them, trying to bring life back to them again. Sitting on the wet ground, Enki didn't think he could even remember what warm felt like. What dry felt like. He wondered if Castiel felt any of it.

They never talked about it but Castiel would always lay his hand on Enki's shoulder or on his arm and the cold would recede, the pain of the day would lessen, and the continuous ache in his shoulder would fall to nothing.

It was these strange, unlooked for gestures that told Enki it was still worth trying to convince Castiel to help them, no matter how many times he said he couldn't.

It was obvious that Castiel did care.

"You're not an evil murdering asshole," Enki said. "I get that, Cas. Except, you know, where you _are_."

Enki couldn't see it, but he could feel Castiel shift so that he was leaning back against the wall, his head tilted to the sky.

"Why do you always do that?" Enki asked. "You always look up, and then that's it; no more from Castiel the guardian who sucks at guarding anything for the rest of the night."

A long pause, and Enki gritted his teeth because every fucking conversation they had seemed to end this way. Except this time Castiel replied, "I pray."

"You pray?" Enki was surprised, because why the hell would any creature as powerful as Castiel need to _pray_? "What for?"

"You cut me off from Heaven. I pray for guidance."

Enki was sure there was more that Castiel wanted to say, but with sudden clarity Enki realised that Castiel was _afraid_.

"You think," Enki said slowly, "Just by helping us this much you're disobeying."

"Understand," Castiel tried to explain, his voice low and urgent as though he was admitting to some terrible secret, "I follow orders. Nothing more. I was not made to decide my own course of action."

It was a life Enki both could and couldn't understand. For so long he'd followed his dad's orders without hesitation or thought, never doubting them, but he'd learned that no one was infallible, that nothing and no one could be right all the time. Not even whatever it was that Castiel prayed to.

"But you can," Enki pushed. "And you can see that this is wrong. I mean, look around you-"

"I must have faith that there is a greater plan," Castiel insisted.

"But you can't see it, can you? This greater plan? How could anything come out of this freaking misery?" Enki knew he was taking a chance in challenging Castiel this much, but Enki hadn't missed the fact that Castiel no longer defended his actions, no longer offered peace in some unknown, unknowable afterlife like it was some kind of consolation. "These people want to live," Enki went on when Castiel said nothing. "They pray to the gods to keep them breathing, not for some awesome life after death."

There was a pause before Castiel shook his head, sounding irritated when he asked, "And what would you have me do?"

"Stop this." Enki held his hands out, palms upwards, feeling the cool rain against his skin.

"I can't stop what has been started. I can't go against Heaven. I am one angel. What could I possibly do?"

"Me and Enlil, we've fought against things bigger and uglier than ourselves all our lives and we've always won," Dean told him. "I took you for a lot of things, but I never took you for a coward."

Castiel hadn't shown even a hint of fear in the face of the demons back in Eridu. He hadn't needed to ask for help when they'd fought a band of _Rabisu_ along the road just past Larsa, nor when a _Lamashutu_ , the worst of all creatures, had attacked them late into the hours of darkness. They'd still been walking, looking for some kind of shelter where none was to be found, exhausted, and Enki was sure both he and his brother would be dead if Castiel hadn't pulled his shiny knife from wherever he kept it hidden and killed the creature. His movements, swift and efficient, spoke of practice and experience and Enki had to admit that Castiel was good in a fight.

"You call me a coward when you know _nothing_ -" Castiel's voice was rising and Enki didn't have the patience to keep it down. Right then, Enki didn't care if the entire fucking world heard them. He knew he'd woken Enlil, his brother shifting beside him.

"I know _nothing_ because that's about all you've ever told us," Enki shot back. "You won't say what's doing this. You tell us you can't stop it, but you don't explain _why_. Don't expect me to just-"

"Enki," Enlil interrupted, sounding wide-awake and tense. He laid a hand on Enki's shoulder. "Maybe you should get some rest."

Enki shook off his brother's hand. "Yeah, no, Enlil. I'm done with dancing around him. He knows what's going on. If he won't help us, the least he could do is tell us what we're up against."

Castiel narrowed his eyes. "The least I can do? I owe you nothing. You imprison me and expect me to be sympathetic?"

Pretty much every conversation they had ended up in some kind of argument, but it had never been this personal before. Enki had never been this pissed at Castiel and he knew it was because he was kind of starting to like the asshole. He just couldn't reconcile the Castiel who helped old ladies carry their belongings with the cold-hearted monster responsible for trying to destroy them all.

"I expect you to not be a murdering asshole. Is that too much to ask? You want me to ask nicely?"

"I'm not," Castiel denied, and tightened his hold on Enki as though he was trying to make a point. "I _can't_."

" _Then tell us how_ ," Enki yelled.

Silence then, and a sudden flash of lightening showed the faces of the other refugees turned towards them, watching in shock and hatred and confusion. "Fuck," Enki swore under his breath.

"We need to get out of here," Enlil urged, already pulling Enki to his feet. They'd done this before too; been forced to leave some temple, or some house, or some shelter by people too scared of them to let them stay. This, though, was a whole new level of messed up. Enki could see murder in their eyes. Close by- too close- Enki could see one man hefting his axe.

"Yeah," Enki agreed. "And fast."

They moved quickly away, out into the night and the full strength of the rain, driven into them by a strong wind. Enki didn't dare try to find another place to stop. He didn't know how much those people had heard and he couldn't be sure they wouldn't follow. On their long march to Girsu Enki had seen temples ransacked and burned, people turning on each other, putting blame wherever they could. Fear and panic had driven people crazy and to give them an excuse, a real excuse, would be suicide.

Enki didn't speak to Castiel throughout the long night, and for once he was glad for Castiel's silence.

***

The gates of Girsu were huge, ancient things decorated with strips of polished copper which gleamed in the sun like gold. Now though there was no sunlight, and the gates, like everything else, had turned grey-yellow, thick with mud and dulled by rain.

The gates were closed, and no amount of pounding on the heavy wood, no amount of pleading, nor bribes offered to the gate keepers would open them. A makeshift town had grown around the city walls in the few days since Enki and Enlil had last been at the city, and Enki was surprised by the sheer numbers of people who had come to this place for sanctuary. Shelters made of animal skins and rocks and whatever else could be found stretched far beyond the boundary markers. Enki and Enlil, with Castiel in tow, walked the churned up path to the city bordered on both sides by makeshift homes and saw families who were hungry, cold and afraid.

There was a huge, angry crowd at the gates and no obvious way of getting into the city without being trampled or torn to shreds or both.

"You think they'll let us in if we say we're just here to use the library?" Enki asked dryly. Enlil snorted and drew the skins he was wearing more closely around his shoulders. Enki hadn't actually thought it possible, but up here in the higher lands it was colder than ever. There was just no fucking end to this misery.

Enki almost jumped in surprise when Castiel said, "I can take us inside."

"Feeling helpful when it's got something to do with releasing you from the spell, huh?" Enki didn't try to hide the disgust in his voice.

They stood in awkward silence, the rain falling around them, filling the deep footprints in the mud with water.

"Yeah," Enki said. "That's what I thought."

They weren't helping anyone standing out here though, and there was always the slim chance that there might be something in the temple libraries that would help them stop this. Not that they hadn't already looked through the tablets a hundred times already. Maybe the priests would be able to point them in the right direction now that they knew a guardian spirit had started it. Now that they knew Heaven meant to drown the world.

He looked to Enlil, and Enlil nodded, probably thinking along the same lines because even if they had nothing like the information they needed, they had a place to start. Castiel could work out the counter-spell his own damn self.

Meeting Castiel's eyes, a challenge, Enki said, "Do it."

Over the past few days Enki had become almost used to this staring. So many times he'd almost asked Cas why he always looked at him like that, and pretty much only him, but Enki wasn't sure he wanted to know.

Enki didn't look away as Castiel reached his arms out, gripping both his and Enlil's shoulders tightly. For less than the blink of an eye the world disappeared but in that time Enki thought he heard the sound of wings beating, the world yanked out from under his feet, the feel of wind through his entire body like he'd been turned inside out. His stomach turned and turned and then the world and the rain were there again. Enki felt himself stumble, his insides knotted like he'd been out for a night of cheap date wine. A hand steadied him and Enki shook his head, trying to regain his balance. The hand was Castiel's and he would've liked to have shrugged it off, but he wasn't convinced he'd keep upright if he did. Beside him, Enlil looked about as ill as Enki felt.

"You could've warned us," Enlil said.

Castiel tilted his head. "I have never transported humans before. I didn't know it would affect you this way."

"Whatever." Enki really wished he could sit down. If they hadn't had a world to save Enki might just have sat straight down into the mud.

"Come on." Enlil was looking around them nervously and Enki saw why. Inside the city the streets were pretty much deserted. Enki could hear the cries from outside the walls, but here, standing on the other side they sounded muffled, dampened. The quiet was eerie and disconcerting and the complete opposite of how Eridu had been. All they could hear was the sound of the rain and the wind breaking against the buildings around them.

Enlil said, "They must have seen that." And then Enki felt it; eyes watching them from the windows and doors of the houses around them. Enki would've bitched at Castiel for landing them right in the middle of a residential area but they had to move. He didn't want to find out how the locals would react to Castiel's magic.

"This way." Enki grabbed hold of Castiel's wrist, pulling him towards the central avenue. From there it would be easy to follow the main thoroughfare to the temple gates. They knew their way to the libraries well, standing in the shadow of the great temple, and that was something you couldn't miss; the stone, step-pyramid shape of it rising above the roofs of all the other buildings in the city.

In a way he hadn't back at the temple in Eridu when he'd had first appeared, now Castiel let Enki drag him along. They moved quickly, away from the city walls and into the narrow maze of homes and streets that made up this district of the city. These streets were usually teeming with people but now they stood deserted and silent. With every step Enki could feel eyes watching them.

"Let us do the talking," he told Castiel under his breath. "The priests at the library know us." And now was not the time to be getting thrown out.

"Enki," Castiel said in a low voice. It was the same tone he'd used the night before when he'd said _of course_ he wouldn't choose to start the end of the world. That he was _sorry_. It reminded Enki how pissed he was, and made him angry at himself for expecting anything more than crap from a supernatural being.

"What?" he snapped.

"I wish there was something more I could do-" Castiel began.

"Wishing isn't going to help us, Cas," Enki cut in. He didn't want to hear his platitudes. He really didn't.

They turned up onto the main street, the avenue widening out, and still they saw no one. Not even any guards or soldiers. No one called to them or questioned them. Enki couldn't blame people for staying inside in this weather, out of the rain and the storm.

Out of nowhere, Enlil frowned at Enki and said, "Cas?"

"What-"

"You called Castiel 'Cas'." Enlil turned to Castiel. "Didn't he?"

"Yes," Castiel confirmed and Enki thought, _what the hell?_. Since when did he give the things he and Enlil spent their life fighting against nicknames? He hadn't even realised he was doing it, and now Enlil was giving him weird looks.

"His name is too long," Enki said, and decided it was true.

Enlil didn't look convinced, said, "Right," in a long drawl, and Enki was about to tell his brother he could fuck right off with his sarcasm when he smelled something burning. On any other day that wouldn't be so weird but in this rain, the air and ground saturated, Enki was sure there wasn't anything left dry enough to burn anymore. It didn't smell like some hearth-fire either, but something thicker and heavier. Larger. But Enki couldn't see any smoke.

"You smell that?" Enki asked.

Enlil sniffed the air. "Fire. In the direction of the libraries."

Exactly what Enki had been thinking.

They both broke into a run and Enki trusted that Castiel would be forced to follow. It was difficult to move fast, to keep their footing on the slippery, thick mud, but they didn't have far to go. Within the temple boundaries there was not a priest or a guard to be seen. The dedication fires lining the road to the temple had become pools of dirty water, the bricks lining the pits covered in mud and dirt where usually they were kept pristine. Offerings and prayer tablets lay broken, abandoned and half-buried in the ground. With every step the smell grew stronger and then, turning the corner at the hostelry the libraries came into sight ahead of them, ablaze. As soon as Enki saw it he knew there was nothing natural about this fire. There was no smoke, and the colours of the flames burned greens and blues. There was no panic, no priests running around nor soldiers trying to create some semblance of order, trying to save the buildings and their irreplaceable contents. There was no one at all.

Enki came to a stop.

"Where the hell is everyone?" He looked around, not believing that the townspeople, the scholars who had spent their lives building this place up, would just let it burn away to nothing. Not even in this weather under these circumstances. If anything, surely the priests must have known that the ancient scriptures housed within the libraries might be the only thing that could save them. "What the fuck?"

"They can't see it." Castiel stood beside Enki, his eyes following the strange flames, seeing more than Enki could, he was sure.

Enki didn't miss the way the flames never crossed the boundary of the doorway, never touched the wooden doors. It could have been the rain but Enki didn't think so.

"Do you know why not?" Enlil asked.

They both watched as Castiel looked behind them, then back to the burning buildings, the doors hanging off their hinges as though they'd been thrown wide open by some inhuman strength.

"There are demons here," he said finally, and Enki should've guessed.

"Is this even real?" Enki couldn't see a way for only the three of them, or only him and Enlil at least, to battle a fire like that. He was about to call for help, to cry fire and see if anybody actually dared answer their alarm, but the added threat of demons made him pause.

"Yes. But specific to this building," Castiel said. "It is a cursed fire."

"The people inside-" Enlil began.

Castiel dismissed, "Are all dead or possessed."

"Possessed." Enki scoffed, "Like that priest you're wearing."

"You pulled me into this body. It was not my choice." Meeting Castiel's eyes was a familiar thing now. Castiel was angry and Enki wasn't ashamed to admit he liked being able to draw emotion out of the spirit, so much of the time aloof and untouchable. Enki liked that he could get behind that facade, to find a real, living creature beneath who _felt_.

"Arguing isn't helping, guys." Enlil, always the voice of reason.

They both knew there were always a ton of people inside the libraries. Maybe more, sheltering from the rain and the storms and the evil and believing the gods would protect them. And now there was no one. Enki wasn't going to accept that.

"There has to be some alive. We can exorcise them-" Enki argued.

"You can't," Castiel said.

It was like Castiel knew exactly how to get to him every damn time. "Man, _no_. We have to at least try, or else what the fuck is the point?"

Since meeting Castiel there had been so many times when Enki would've loved to punch Castiel in the face. Maybe if he'd thought it would do any good he would have.

Shaking his head, dismissing Castiel, Enki started forward, meaning to get closer to the open doorway to see if there was anyone inside or any way in. Castiel caught his shoulder and held him back, his grip effortlessly strong.

"You shouldn't go in there," he said. Enki looked back, meeting Castiel's eyes and holding them, challenging Castiel to stop him. To help him. To do _something_.

It shouldn't have been a surprise when Cas just stood there, staring back, his face blank. Enki shrugged his hand away and turned to his brother.

"Enlil," he said, and his brother nodded.

Together they hurried towards the burning library. This close Enki should have been able to feel the heat from the flames but there was nothing, just the same steady, cold rain.

Enki called out, "Is there anyone inside?"

Beyond the doors he could make out the stacks, the wooden shelves ablaze. The roof was charred black. Inching closer, holding their wet skins up in front of them for protection, they moved through the entrance and instantly on crossing the threshold a wave of heat and thick smoke, choking and burning, hit Enki so hard he staggered back.

"Shit," he swore. The heat made the skin on his bare arms feel like it was peeling away and he could smell singed hair.

"We can't go in any further," Enlil called. He had his skin pulled up to his face, coughing.

It was frustrating. They'd hardly gotten anywhere at all, and to give up now when there might be people inside who needed their help was almost unbearable. Somewhere inside a stack collapsed, its heavy piles of tablets smashing to the ground. The information they needed might have been in there for all they knew. And how the hell were just the two of them supposed to take on a fire of this size anyway?

Then, Enki could've sworn he heard a cry for help. He looked at Enlil who had his head tilted up, listening, so Enki knew it wasn't just the smoke getting to him.

A few minutes ago he'd have given anything to be warm, but not like this, and now he longed to be back out in the cooling rain.

"We have to," Enki said, because they couldn't ignore whoever was trapped inside. It wasn't what they did. They didn't have much to lose anyway.

"Yeah," Enlil agreed, and they pushed forward, around the burning shelves, trying to stick close to the walls and the windows. Even beneath the vents high in the ceilings Enki didn't feel any air coming in or going out, like the entire building was closed off from the outside world somehow. He wondered at how they'd been able to smell the fire at all.

The flames licked at their feet, burning at their bare soles and Enki moved faster.

They passed the body of what had once been a priest lying slumped against a wall, his fingers outstretched like he'd been trying to claw his way out of the building. It was hard to tell if he'd been someone they knew or not because one side of his body was blackened and charred and unrecognisable. The smell of burnt flesh was strong and Enki was sure there were other corpses nearby.

They kept moving, hearing the cry again. Two cries. The beams above them creaked ominously. Enki knew better than to waste his time bothering to pray that the ceiling wouldn't fall in on them. Beside him he could see Enlil's eyes scanning the shelves, grimacing in the face of all the knowledge that was being lost. Enki knew as well as Enlil that they'd never make it back to Nippur before it was subsumed with water at the rate the rivers had been flooding in the lower lands. Maybe the city was already gone, taking with it any chance of breaking the spell on Cas.

Then, there was a loud cracking sound as part of the roof gave way and Enki pushed Enlil hard up against the wall, automatically shielding his brother with his own body. The debris fell close to them, burning timbers hitting Enki's back, singeing and tearing and he cried out. This, Enki thought, had been a stupid idea. It had been a desperate, foolish thing to do and now they were going to die here. They hadn't saved anyone.

He crouched closer to Enlil as more roof fell in, sending up thick, fine, choking dust. Flames that burned blue and unnatural sparked around them, more ferocious, hotter and hotter and closer. Enki pulled the skins more tightly around them ignoring the heat at his back and the smoke and smell in his nose.

He was sure this was it, their last moments, and couldn't think of anything to do but to try and stay alive just a little longer. Enki hung on to his brother and hoped against hope that something would come to him like it always did when it came down to it. Not this time though. There was a deafening snapping directly above them and Enki knew that was it.

The blow- the end- never came.

Suddenly the heat wasn't so pressing, the smoke in his throat not so thick and choking. He looked up to see Castiel standing over them. The roof was so completely caved in that Enki could feel the rain against his face. There were red lines that couldn't be anything other than burns streaking across Castiel's arms. Enki saw that Cas's hands were patched with red and black cracked skin as he turned, bending down to pick up the burning timbers closest to them, throwing them away. Parts of the priest's robes he wore were peppered with holes, the edges stained with soot, and Enki watched him move, tossing rubble and wreckage aside like it weighed nothing, lifting his arms and whispering unfamiliar words under his breath so that the flames backed away, abated.

"Cas," he said in shock and awe. Enki would never have guessed that Castiel would be the one to save them.

"You forget," Castiel said, but there was amusement in his eyes, "I can't _not_ follow you."

Enki looked back to the door, and yeah, he guessed it was true that it was way beyond the distance the bond would let them be apart. But Castiel was keeping the fire back, and he was clearing a path towards the inner part of the library, not back towards the outside.

"You are insufferably stubborn," he said, and held out a blackened hand to Enki. He took it gladly, pulling Enlil up to stand beside him. His brother was hacking and coughing, his eyes streaming red from the dust and soot in the air but he was grinning and watching Castiel too.

"We're saving those people," Enki said, just to be sure this was real, and Cas nodded.

"Yes."

He held on to Cas's hand as he was pulled along, looked down at the blisters on it. "That's gotta hurt."

Castiel glanced curiously at his own borrowed skin. "It will heal," he said. Then added, "But yes, it hurts."

"Me holding your hand is making it worse," Enki pointed out, and Castiel let go, nodding.

"I can't hear anyone," Enlil noted and he sounded cautious, like he didn't want to interrupt but he had to. Enki realised he'd been staring at Cas again and Cas had been doing the creepy staring back without blinking thing. How- why- they always ended up doing that Enki didn't know.

It was weirdly difficult to look away, but there was a fire blazing around them and the building collapsing in on itself.

Towards the next room the roof looked mostly intact but the fire more fierce and out of control. Enki couldn't hear the voices crying out for help anymore either.

"Can you get us further inside?" Enki asked, because Castiel was somehow holding back the flames, the heat, and the choking heavy air. Enki could see the flames and the smoke surrounding them but none of it touched them.

Castiel's jaw tightened as though he were debating with himself and for a moment Enki thought he was going to refuse but then he agreed, "Yes," and Enki couldn't help but grin.

Castiel ignored him and turned away again, commanding them, "Stay close."

They passed through the doorway, the doors themselves almost completely burned away. Ducking under the fallen door mantel they came out into the smaller back room. Here the most rare and the most sacred tablets were stored. Most of them lay broken or smashed to dust. Useless. It wasn't going to do any good to think of what they were going to do with the library gone. It was better to concentrate on the present. Castiel pushed a half-collapsed shelf aside, not seeming to care about the tablets he broke in the process. They'd be charred now anyway, and if they survived it would take work- work taking way more time than they had- to make any of them readable again.

Moving deeper into the room Cas pushed aside burning shelf after burning shelf and Enki kind of wanted to tell him to stop- to tell him that they could go around- because his hands looked more and more painfully burned. They searched all the way to the back wall where they finally came across a body caught under a mass of brick and beams where part of the wall had collapsed. It was a priest, a young novice by the looks of him. He wasn't moving.

"He's alive," Castiel said, moving aside debris before crouching down beside the young priest. Enki felt useless, because he couldn't touch anything without burning himself and he couldn't lift anything so heavy. Beside him Enlil was as restless, as impatient to do something as he was. Enlil leaned over and Enki got onto his knees, careful of the sharp edges and the hot embers around him, made to pull the priest guy out as soon as he was free, but then there was an inhuman screech and something was barrelling straight towards Castiel. Its eyes were black and it had blood on its lips.

Enki could see what was going to happen, and Enlil must've too because he made a grab for the priest's shoulders and starting pulling as hard as he could. They got him out and dragged into the far corner just before the demon rammed into Castiel's chest, knocking him over and sending him crashing to the floor.

For an instant there was unbelievable heat and smoke and it fucking _hurt_ , but then it was gone and Enki realised for that short time Castiel's concentration must have gone, exposing them to the fire.

Enki watched as the demon waded through the fire as if it was nothing, made straight for where Castiel had landed and started pounding on him with its fists.

He heard it hiss, "Bright, pretty Heaven creature," and its cracked, bloody lips curved into a crazed, gleeful smile. It laughed as Castiel hit out and something had to be wrong because he couldn't get a hit in, his punches weak. When he'd fought the demons in Eridu they'd been nothing to Castiel, but this demons was tightening its hands around Castiel's neck, squeezing and squeezing and laughing. Enki heard Castiel actually gasp like he needed the air. It was something Enki had never heard from Castiel before and it freaked him out.

Whatever Castiel was doing to keep the heat away from them was fading too. Enki could feel his arms prickling, the air heavier. Cas was losing.

Enki had no holy water and he'd long since run out of salt. It was all gone, had all been used up days ago after fighting monster after monster after monster. He had his knife though, and Enki didn't even think before he was moving forward, drawing out the blade and feeling the comfortable, familiar weight of it in his hand. He ignored the flames and the building collapsing around him and before he could consider all the ways this could go wrong he was driving the knife into the demon's neck.

It reared back, lashing out at Enki and knocking him over hard. Enki fell onto his back among broken timbers and sharp edges and it hurt. But Cas was still down, so Enki fought his way back to standing in time to see Enlil attack the demon. His knife had lodged into its throat and Enlil pulled it out, stabbed the demon in the neck again, slit its throat, making it impossible to remain in the body anymore. This demon was stubborn and had to be powerful because it clung on to life, grasping at Enlil's leg to try and pull him down. It might've worked, and Enki was lunging forward to stop the fucker getting to his brother, but then Cas was there, his palm pressed to the demon's forehead. There was the same bright light, though this time slower to build and Enki could see that Cas was gritting his teeth, his eyes focused on the demon in concentration. The demon wailed and screamed and Enki could see the fury in its eyes, filling with that blinding whiteness. Enki could tell the moment it was gone, not just exorcised but put down for good. The body of what had maybe once been a scholar going limp, the light disappearing to nothing leaving only burnt out eye-sockets and a buzzing sound in Enki's ears.

Then the world returned and Enki remembered where they were and what they were doing and how screwed they were.

"Enlil," Enki called, "The priest." His brother was already on it, calling back, "Yeah, yeah. I know what I’m doing."

Enki ignored the comment.

Castiel had collapsed back into the debris and Enki went to him. The burns looked bad and there were bruises swelling across his cheek. Castiel's eyes were screwed tightly shut.

"Cas," Enki said, gathering into his arms the body of a priest whose name he didn't even now but now would only ever be _Castiel_. He was light, and a lot smaller than Enki had imagined. Castiel always seemed to fill the air around him as well as the body he inhabited and it was weird to see him like this; reduced, fighting for breath.

He thought about how many others had been killed in the library, how many they couldn't save. This time they were barely getting out of there with their own lives.

Enki didn't fail to notice that the heat, the flames and the smoke were still being driven away. By the wall Enlil was huddled around the priest they'd found alive. He was breathing fairly normally so Enki guessed whatever was keeping him from burning alive extended to his brother too. And that could only have been Cas's doing.

"Okay, okay," Enki conceded. "We're out of here. Just, Cas, open your eyes."

It was weird, but Enki wanted to see them to know for sure that Cas was good.

When slowly, painfully slowly, Cas's eyelids slid open Enki felt a relief he'd never imagined he'd ever feel for a supernatural being. He was supposed to hate them. All of them. But Cas had saved their lives, and somewhere along the line Enki had gotten used to his presence and his quiet annoyance at pretty much everything ever.

"Hey," Enki said, and Castiel sort of almost smiled.

"I don't like this fire," Cas replied testily. Enki wondered if maybe there was something in the fire sapping Castiel's strength.

"Me neither man," Enki grinned back. It took most of Enki's strength to pull Castiel to his feet and drag him over to where Enlil was holding a rag against the side of the young priest's head. It was already soaked through with blood.

Their options were limited. The building was obviously on the verge of collapse, creaking and groaning ominously. They were exhausted and all around them the flames grew taller, burned hotter, out of control. The way they'd come was blocked by a mass of debris and fire.

Castiel seemed to realise the corner they'd backed themselves into because he announced, "I will remove us from this place."

Enki was taking one hell of a lot of Cas's weight and he could see livid purple bruises imprinted around his neck. If it had been anyone else Enki wouldn't have believed them capable of doing _anything_ in such a bad state. Even if Enki had wanted to stay to keep looking for more survivors he wasn't given the chance to protest because between one breath and the next he was outside. In front of him, Enlil was still curved protectively around the priest. It was still raining. Castiel collapsed against his side, dragging Enki down into the mud. It felt good beneath his knees. They were all still breathing so Enki let himself relax, just for a moment, leaning against Castiel as Castiel leaned against him in turn.

It wasn't a win. Out of maybe twenty or thirty priests Enki knew who worked in the library they'd saved only one. But they'd all gotten out of there alive and in one piece, just barely, so it wasn't exactly a failure either.

It was still raining. They'd gained nothing. But Enki couldn't bring himself to care.

***

"It is an _Asag_ ," Castiel said. He kept his voice low so that the sound didn't echo around the room. In the far corner, Enlil was talking to a bunch of Elders. They kept looking over at them with strange looks. None angry or vengeful though, so Enki let himself relax slightly. "When it's released it brings ruin," Castiel went on. "It is both omen and instigator."

Enki hadn't even asked anything, and maybe that was the point.

Cas was laid on the cold stone of the temple floor, Enki sitting next to him, and for a long time they hadn't said a word to each other. Cas looked wiped but the burns were healing and the bruises were almost gone, and Enki was glad for that.

"You can't stop it," Castiel said. "And neither can I."

The way Castiel closed his eyes and turned his head away made Enki think that maybe he wanted to though.

"It's a monster, right?" Enki asked. In the lore, somewhere in the past, he was sure he'd heard the name- _Asag_ \- before. It was a stone creature, he remembered. It was so hideous it made rivers boil. It hadn't been seen since before the time of the gods. "If it's a monster, we can kill it. That's what we do." There was nothing he'd ever come across that couldn't be weakened, hurt and ultimately killed.

"You can't." Castiel sounded so tired and so resigned that Enki put a hand lightly on his shoulder. He kind of wished they'd met under better circumstances. That Cas really did look like this young priest instead of just inhabiting his body, his true self an unknown thing that, according to Castiel, would burn his eyes out if he saw it. Enki remembered those wings, arching black shapes across the temple walls in Eridu, filling the room. Sometimes, Enki caught Cas looking over his shoulder and he couldn't help wondering if Castiel was checking his wings were still there or something.

"You know we have to try." Cas had been travelling with Enki and his brother long enough to know that they'd never just let this go. They'd never give up and run away. He wasn't even sure they could anymore. When they'd been moving Cas from outside of the library into the temple he'd heard some of the junior priests talking and what they'd said hadn't been encouraging; a messenger hadn't been able to find a way down to the lowlands, all the roads and paths flooded. The steady stream of refugees making the trek up to the city had trailed off to nothing. Enki didn't want to think about what that meant.

Instead, he turned to watch his brother. Enlil was arguing with the Head priest, a small, over-fed man with a red face who frowned sternly at them all. Enki guessed it had something to do with the binding spell because Enlil kept pointing emphatically at Cas. They'd decided after the library that the spell had to go. It weakened Castiel, ultimately the reason he was lying here now on the floor of a temple looking small and human, without the strength to even sit up.

He gave him water and Castiel drank for the first time Enki had ever seen. He sighed in relief at the taste and thanked Enki. As night came Castiel had shivered, his teeth chattering, and Enki had found dry furs and draped them over Castiel and around himself and shouted at Enlil to wear them too. They'd all been cold for so long. Enki had marvelled at the feel of something that wasn't sopping wet against his skin. It was still kind of weird not to have the steady beat of rain against his face and his shoulders and his arms. He would swear he could still hear the hissing sound of rain falling around him.

Cas hadn't said anything but Enki knew the spell was preventing him from healing too. Enki had heard stories of Guardian spirits skewered by arrows and spears who had walked away without a scratch. Carved into the walls in front of him a great winged figure almost seemed to glare down at Enki and he had to admit that yeah, okay, this was kind of his fault. Except where Cas had started it. Everything was all so fucked up.

But now Cas had told him what was responsible for drowning their world, maybe he'd tell them how to stop it too. With Cas at full power maybe they'd even succeed.

Even with his head turned away Cas somehow picked up on what Enki was about to ask because he said, "Don't ask me to help you." Enki was fairly certain Cas couldn't read his mind but he still shifted uncomfortably.

"Why'd you tell me about the _Asag_ then? Why bother?" Enki demanded to know.

"To convince you there is nothing you can do." Then Cas did turn to look at Enki and shit, his _eyes_. "I could take you and Enlil away from here," he offered and Enki couldn't decide if he loved him for that or hated him. He knew what his answer _should_ be. He knew what answer everyone would expect of him, but he could save Enlil and he could save himself and maybe he would get to see Castiel again. He couldn't leave while there was a chance though. Not while there was still hope.

Enki shook his head and was going to tell Castiel that no, that wasn't how they did things, but then Enlil hurried over and crouched down beside them. He had a triumphant smile on his face, the kind he that told Enki he'd worked something out, like when he knew what they were up against and how to defeat it.

"The head priest says he knows something that might undo the spell," he announced, and grinned triumphantly down at Cas. "You'll be okay, man." And shit but Castiel smiled back. It wasn't much, but it was something and it was real, like actual human emotion.

Sounding relieved, Castiel said, "Thank you, Enlil."

"You gonna disappear on us?" Enki asked. "When the spell isn't there anymore?" He wanted to believe Cas was going to hang around and save them. When it came to it, Enki thought, he wouldn't let them die.

"I should." It wasn't an answer but then in the whole time Enki had known Cas, he hadn't given a single straight reply. It sounded to Enki like Cas didn't know what to do.

They waited as the head priest approached, dressed in all his finery of gold and purples. He bowed low to Castiel, so much so that his perfect white robes touched the muddy floor. Enki wondered how he'd managed to stay clean for so long. The priest looked awed and wary. He had, after all, been one of the priests who had encouraged them to bind Castiel.

"I apologise for our audacity," he said, his voice trembling. "We beg the forgiveness of Heaven."

How the head priest could find Cas even slightly scary like this Enki didn't know. His eyes were half-closed, tired, his arms streaked with mud and ash where they lay against the skins. His hair was a mess, like he's just woken up. Not exactly a picture of divine retribution. But then, they were about to give him back all his strength and what he did then was anyone's guess. It was weird but Enki didn't believe Cas would hurt any of them.

The head priest carried a bowl, enamelled with intricate spells and Enki recognised it as being almost identical to the bowl he'd spilt blood in to bind this spell. Back then Enki very clearly remembered saying this was a bad idea.

With his free hand, the priest drew a knife from his belt and Enki sighed because he really should've seen that coming. He offered up his palm. Out the corner of this eye Enki could see that Castiel was watching him.

The priest hesitated, the blade hovering above the flesh of Enki's hand. He was staring at him, looking uncertain. Priests, Enki had often found, particularly those high up in the order, were more concerned with keeping their own skin intact than pretty much anything else.

Enki nodded and even though the priest didn't look convinced he closed his eyes, began speaking under his breath. Enki winced when he felt the pinch of the knife along his palm.

He didn't know if freeing Cas would help save them. They should've been spending what time they had left looking into where this _Asag_ thing was and finding a way to kill it. But first Enki would release Cas from this binding spell because he wasn't cruel, and somewhere along the road to Girsu Enki had started thinking of him as a friend.

It was a long time before the priest fell silent and all the while he drew off more and more of Enki's blood until he felt dizzy and sick. The incense wasn't helping. But Cas was there beside him, a solid presence, leaning into Enki's touch, and with every drop of Enki's blood and every word the priest chanted Castiel looked stronger, colour returning to his face, the burns along his arms receding.

The air in the room became heavy and oppressive and Enki remembered this from before too, when they'd first summoned Castiel and he'd been something blindingly bright and unknowable. There was no light this time. It wasn't so much that the light in the room lessened, but more that colour itself dimmed so that the world looked grey and flat. It was freaky as hell. Enki had to rub at his eyes because everything around him was merging into one dark mass of indistinguishable shapes. Whatever was happening set his teeth on edge, made the hair rise on his arms. Where he touched Cas's shoulder was warm.

The priest resumed his chants, faster and louder and less like language and more like sounds. There was a tearing sound, a splitting, and Enki thought for a moment it was the building falling down around them. _Again_. Suddenly the sound cut off, the air tasted familiar again, and colour returned to the world, vivid and almost overwhelming after its absence.

No one spoke. No one moved. The only sound came from the pounding of rain against the door, the crackle and hiss of the lamps casting flickering shadows across the decorated walls.

Castiel sat up and Enki let his hand fall away. There was something different about him; his presence suddenly distant and removed and Castiel looked up towards the ceiling, tilting his head as though he were listening. He was cut off from Heaven, he'd said, and Enki wondered if that's what he was listening to now. If Heaven was ordering him to kill them all.

Enki found himself weirdly pleased when Castiel looked back down and straight at him, staring in that familiar freaky way. At least, Enki though, Castiel remembered who he was even now that he was an all-powerful Guardian spirit again.

In that same voice that wasn't his voice at all, Castiel said, "Enki."

"You're not gonna smite us then?" Enki quipped, because it was easier than thinking that Castiel might.

Cas gave one of his almost-smiles in reply, and it was good to have evidence that he still _felt_. "No."

Reaching out, Castiel's fingertips touched Enki's cheek, light and warm and Enki could feel his head clearing, the sick feeling of losing too much blood and being too hungry and cold for too long and walking too far and breathing in smoke, all gone in an instant. For the first time in days, maybe in weeks, Enki actually felt pretty good. Pulling himself to his feet was easier than it had been in years. Enki grinned, "Thanks," and meant it.

He offered a hand to Castiel, still sitting underneath the piles of pathetic skins he'd scraped together and Castiel took it. There was no way Cas actually needed the help; Enki could feel the strength of his grip, and he watched as Castiel stood with a fluidity and grace he didn't think he'd ever seen in a human. It was weird though, because Cas still had the same messed up hair and the same muddy, burnt clothes. Maybe be just didn't care about his appearance. Maybe it was beneath him.

This was it, Enki thought, and even though he didn't want to ask he knew he had to. "You sticking around?"

Castiel's eyes turned sad but he didn't look away when he replied, "You know I can't."

"I really don't." Enki shook his head and then Cas did look away.

"I must leave this place."

What he wasn't saying, but what Enki could hear anyway, was, _Come with me_.

Enki shook his head again.

Close by, Enki could feel Enlil and the head priest watching them. He had responsibilities. He couldn't let his world die without a fight.

From the way Castiel straightened, as though he were stretching limbs Enki couldn't see- _wings_ , Enki realised- he understood that Castiel was readying himself to leave. After everything, Enki couldn't just let it end like this. There was nothing much left to lose anyway.

"Tell us where the _Asag_ is? Tell us how to kill it?" Enki begged, because the air was shifting in the room and Enki knew that Cas would be gone in a breath. He's never once begged before. Not for anything. He'd never imagined he would, but if ever there was a time to forget his pride it was now.

"Don't ask me that," Castiel said, seeming to sink back into himself, and for the first time Enki wondered what would happen to the young priest Castiel had been wearing for the past few days when he left. Cas had been burnt and stabbed and he hadn't eaten, nor drunk, nor slept. He hoped the poor guy hadn't felt any of it.

"I have to, Cas. Tell me," Enki insisted. " _Please_."

"You can't kill it. _I_ can't kill it." He was looking to the side again, the way he always did when he didn't know what to say. When he didn't want to face what Enki and Enlil and the rest of the world were facing.

Enki had no sympathy. He started this, and Enki was going to make him finish it. "We've been through these arguments." They had. A hundred times over and Enki was sick of them.

"I'd be sending you to your death." There was something a little satisfying about how horrified Cas sounded at the thought.

"Instead of just leaving us to our death?" Enki snorted unkindly. He didn't want them to end like this. "If you don't do anything else, at least send me and Enlil to this thing."

He glanced at his brother and Enlil gave a nod. It was good to know that even if all they were doing was going to get themselves ripped to shreds Enlil would at least be there with him.

Cas actually looked distraught. He glanced upwards before looking right back at Enki.

"You'll _die_ ," he said.

"We will anyway," Enki pointed out, and he could see the resignation in Cas's eyes, the sadness of his expression.

Castiel nodded, and motioned for Enlil to join them. "Its skin is impenetrable," he told them as he reached his hands out towards their foreheads. "Its eyes are its weakest points," and without so much as a goodbye the world shifted and changed and in an instant they were somewhere else, and Castiel was no longer with them.

***

Everything Enki could remember about _Asag_ amounted to very little. Even Enlil, who usually found it easy to hold all the stuff they'd ever heard in his head, didn't have much more to offer.

They didn't like sunlight, Enki knew that much, but then neither had the _Rabisu_ and Enki and Enlil had fought a whole bunch of those in broad daylight recently. With the world turned so upside down it was impossible to know what to expect.

Castiel had sent them to the mountains, high up on a rock face looking down over a flooded valley. Here, wherever they were, the rain fell in sheets, a steady pounding of water that set streams running fast around their feet, hurrying down the steep slope. Enki worried that the hillside was unstable, the stone shifting beneath them making it difficult to keep their balance. In an instant they were soaked through again and cold; colder than anywhere else Enki could ever remember being and he felt himself start to shiver. They'd left their cloaks behind. They'd left everything behind except their weapons and Cas's blessing. Enki could still feel the light touch of Cas's fingers on his forehead, the only part of him that still felt warm. When it came down to it Enki trusted that Cas wouldn't put them anywhere dangerous before they'd even had a chance to see this monster so he ignored the instability and the sliding rock and mud and looked around.

The mountainside was an expanse of grey stone and rocks, uneven and sharp-edged. There were caves higher up and Enki guessed that was where the monster had hidden itself away. He looked to Enlil.

"We going up there?" Enlil already had his knife drawn, his feet planted wide, ready to fight.

There was no life here. Nothing green, no birdsong, just the sounds of the rain and rushing water and the shifting of stone against stone, crunching under his feet. Suddenly a roar- a _scream_ \- like nothing Enki had ever heard before cut through the quiet. No human could've made that sound.

Enki reached for his own knife. "Or maybe it'll come to us."

The sky looked washed out, faded to a colour as grey as the mountain slopes so that one bled into the other. It was a shitty place to die, Enki thought.

Another howl echoed out from the caves. Enki couldn't pinpoint where or how close but he knew they wouldn't have to wait long before it came to the fight. This was stupid, Enki thought. Reckless. They didn't even know if they could kill the _Asag_ with the weapons they had. There'd been no time for research, no possibility anyway with the library burnt to the ground. They'd made surviving impossible odds the habit of a lifetime though and Enki just hoped their luck would hold. Now, too, there was Cas. There was a chance he would still come. That he wouldn't let them die.

Enlil said, "Enki," and his little brother, who wasn't so little anymore and hadn't been in a long time, looked at Enki like he was on the verge of saying something stupid like _goodbye_.

"Shut up, Enlil," Enki ordered. "We'll get through this. We always do, right?"

Enlil didn't look so sure, his lips thinning in annoyance. It was such a familiar expression that Enki could almost believe this was any other hunt on any other day. Enki refused to believe they were going to their deaths. If they died, their world drowned. After all the crap they'd gone through and everyone they'd loved and watched die over and over again, if they failed now it would all have been for nothing.

The roaring of the creature was so loud now it hurt Enki's ears. Above them stones started to shift and slide down the mountainside. It might've been from the sound, but more likely it was caused by the weight of the monster and Enki had to wonder how big this thing was. He remembered something about multiple eyes and arms and claws and Enki had a feeling the monster was going to be massive.

They should've brought spears, Enki found himself thinking. Spears and throwing slings and fire, even if it would never have stayed alight in the rain. Maybe a battering ram.

"I just wanted to say-" Enlil persisted, and Enki cut him off.

"Don't you fucking dare."

"But I just want you to know-" Enlil tried again but whatever he was going to say was lost when the creature roared again, _bellowed_ , and this time the entire mountain shook.

It was hard not to give in to the urge to cover his ears and even more difficult to stay on his feet, but Enki did and beside him Enlil kept his footing too.

They kept their eyes fixed on the caves and then they saw it. And oh fuck, but it was _huge_.

Huge and ugly, a mess of all the wrong limbs attached at odd angles to its long, snake-like body. Its skin- if you could call it skin- was as grey as the sky and the mountains around them and Enki wondered if this thing meant to turn the world into an image of itself.

It moved freakishly fast for something so big.

It had eyes all over its body, yellow and unblinking and every single one of them was turned to the sky, unconcerned about the rain. The eyes were the weakest point, Castiel had said, and there were, at least, a lot of them to work with.

Without needing to look the creature knew where they were because its great bulk headed straight for them.

"This is it," Enki said, steadying himself. He'd picked up a bag of salt at the temple and he felt his belt to check it was still secure, made sure his second knife was in its place. All of it seemed so tiny in comparison to the thing bearing down on them. He threw Enlil a quick grin because if he _was_ going to die here then he wasn't going to die afraid.

For the first time in his life Enki prayed. Not to the gods, because what the fuck would they care, but to Castiel who he knew and didn't mind hanging around and would like to see again. He prayed for help and he prayed for his brother and he prayed for the world and everyone in it. _What's the point?_ he prayed to Cas. _If people don't exist, what's the point?_

Enki wondered what would happen if they failed; if he and Enlil died and the creature lived, would the rains ever stop or would the entire universe fill with water until there was nothing left at all? And then, would Castiel get his feet wet? His wings? Would he even notice if the world was gone?

The ground shook again as the monster howled, and what the fuck did it have to complain about anyway? Maybe it was territorial, Enki considered. Maybe it just didn't like humans. It was definitely taking offense to their presence, striking out at them so fast that Enki had to roll away, stones cutting into the palms of his hands and his knees.

The _Asag_ took a swipe at him with one of its long, thick arms, catching him as he tried to stand up and damn but it was like being hit by rock. Enki felt himself thrown back, landing hard against the ground and this was not a good start.

Just in time, Enki caught sight of another arm coming towards him and he scrambled back, throwing himself to the ground and hoping that Enlil was having more success. Or at least that he was spending less time on his ass and more time actually fighting the thing.

Enki stayed down, looking to see which eye would be easiest to target. There was one that was watching him from just below one of the creature's arms and that had to be the creepiest thing Enki had ever seen.

Before he could second-guess himself Enki leaped up and stabbed his knife deep into the tender, wet flesh of the eye. It gave way easily under the blade, splitting and popping and Enki had time to feel satisfaction for all of an instant before the creature was screaming so loudly Enki's head felt like it was going to cave in on itself. It made him dizzy and he stumbled back, disoriented, not able to defend himself when the _Asag_ swept him aside with a solid arm to Enki's stomach. He felt the air punched out of his lungs and the pain of rock hitting his back.

 _Enlil_ , he thought. And then, _Brilliant fucking idea, Cas._

Enki shook his head, trying to clear it, checking he still had his knife in his hand, and somehow against all reason, it was still there.

A sickeningly foul smell filled the air and Enki realised the creature was pretty much right in his face. What he guessed were the jaws of its mouth snapped at him, thin needles that must've been its teeth flashing in front of him. Enki didn't even think before he was reaching for the salt tied to his belt, tugging at it desperately as the monster tried to fucking _eat_ him. With his knife, the blade clinking and rebounding against teeth and skin as hard as rock, Enki tried to hold the thing off but he could feel it ripping and tearing at the vulnerable skin of his arm and oh holy shit it _hurt_.

He thought maybe he heard Enlil's voice shouting his name but it was hard to tell when he was already half-deafened and all his concentration was focused on staying alive.

Finally, fucking _finally_ , the string came loose and Enki tossed the bag as far back into the creature's mouth as he could. For way too long it didn't make any difference and Enki was sure he was going to lose his arm. It was shredded and there was so much blood and Enki didn't want to even look at it. Mostly he was surprised he could still keep a grip on his knife, let alone continue slashing at the creature's mouth, hoping that maybe there was something inside that was soft and vulnerable. But the blade just kept hitting solid stone. It was useless.

Then suddenly the monster stopped moving. A deep gurgling sound erupted from somewhere at the back of its throat like it was choking and it reared back. In that instant Enki felt hands hook under his shoulders tugging hard and pulling him clear as the _Asag_ used its whole head to pound at the ground exactly where Enki had been sitting.

Enlil, Enki realised. Enlil had saved him from getting crushed to death. He looked at his brother. There was blood on his face and he was empty-handed, no knives tucked in his belt. Weaponless.

"Enki-" Enlil said.

"He'll come." Enki was sure of it. He hadn't realised until that moment how much he'd been relying on it.

There was no time for Enlil to reply before the creature was surging forward, its huge mouth snapping at them, enraged.

The salt hadn't slowed the creature. It didn't look like it had done much at all except to make it _really_ mad.

 _Cas_ , Enki prayed, letting Enlil drag him further away, trying to get his feet under him on the unstable ground. He tried to ignore the way the rock slipped and slid away under his feet. Now he was really starting to feel the pain in his arm. It was bleeding too much, red mixing with the rain to create a trail as they stumbled out of the creature's reach.

It was difficult to concentrate, and Enki was aware that Enlil was saying something but he couldn't hear it over the sound of his own blood rushing through his ears. And the pounding rain.

Fuck, he was so sick of the rain.

From what Enki could make out Enlil was trying to get around the _Asag_ , maybe trying to take the higher ground. Definitely trying to get away from the monster's jaws.

"Take my knife," Enki urged. He wasn't convinced his fingers would be able to grip it anymore anyway. As unhelpful as it was proving to be he had a spare tucked in his belt too.

"It's useless," Enlil panted. He was taking a lot of Enki's weight, constantly on the move, trying to avoid the creature's claws and the twisting of its body. "Its skin is hard as rock."

"The eyes," Enki told him. "I got a knife in one." Not that it had helped but it was something. They just needed to get close. It wasn't like they had any other options.

Enki tried to straighten himself up, stand on his own feet. He pressed his knife into Enlil's hand, grimacing at the pain it caused to move his wrecked arm even a little. That knife had always brought him luck. It'd never let him down and it made Enki feel better to know Enlil had it.

His other knife was much older and had once been their dad's. Enki kept its blade sharp and the sigils along its handle and metal clean.

"Eye closest to its head?" Enlil suggested.

"Together," Enki agreed.

This wasn't the end, Enki tried to tell himself even if Enlil was looking at him like he was trying to say goodbye again. Enki looked away. "Let's do this." He sounded one hell of a lot more confident than he felt but Enlil needed to believe they could do this. In the back of his mind Enki knew he was still waiting for Cas to show up. He shouldn't, he knew that. Cas was a supernatural being and he had said repeatedly he wouldn't help them. But Enki still believed he would save them like he had in the burning library.

"Yeah," Enlil said.

Somehow Enki managed to find the strength to dodge the creature's arms and its tail and its mouth as he and Enlil tried to find a way to get in close. Pushing aside the pain and the dizziness and the doubt Enki took the first opening he saw in the curve of the creature's body, its eye exposed and its arms a relatively safe distance away. In that moment Enki launched himself forward and trusted that Enlil would follow.

This time he knew to expect the flesh of the eye to give easily under his blade and Enki pushed in further, sickened by the way he could feel the eye trying to move and the cold wetness of thick liquid surrounding his hand.

Moving in quickly to stand beside him, Enlil stabbed down and Enki watched as his brother's face screwed up in disgust, his arm disappearing into the eyeball. Any other time the expression would've made Enki laugh.

Beneath them the monster tried to jerk away but Enki hung on and Enlil did the same. If they were knocked loose he knew the creature would easily be able to reach them, to crush them or eat them or rip them apart. They were both tiring fast. Enki's arm was too badly cut up to stop bleeding without help. He could feel warm blood sliding thickly across his skin. To make it worse his other arm, driven deep inside the creature's eyeball, was starting to burn. Its flesh, Enki reflected, was probably poisonous.

He tried cutting at where the eye met stone hard skin, tried stabbing deeper inside, frantic and not able to get at anything vital. Enlil was having about the same luck, which was none at all.

Then the _Asag_ heaved its whole body and the movement dislodged them both, knocking them both sideways onto their asses. Enki scrambled away, unsure of his footing or his balance, and when he turned back Enlil was still there. His brother clung to the monster, stabbing over and over and Enki could see how mangled the eye was now; just a mess of ripped flesh, yellow puss streaming from gaping wounds. Enlil stood his ground, reaching right inside the eye, trying to do damage. As he drew his knife back the creature pulled away sharply. It swung back its entire bulk at Enlil, trying to push him away. As the creature's body impacted against Enlil, Enki heard more than saw the knife his brother was holding hit the _Asag_ 's skin and shatter.

"Enlil!" Enki called out. It wouldn't help, he knew, but he had to try to warn his brother. He could see the monster raising its arm, aimed straight for Enlil. His brother had turned away, been forced to his knees and he trying to stand and oh god there was no way Enki could stop it.

He tried anyway, rushing forward and slipping in his hurry, He pushed to his feet again all the while shouting at Enlil to fucking _move_. It was already too late. The creature's arm came down on Enlil and Enki watched in horror as his brother was knocked down by the full weight of the monster's strength. Over its howls and the rain and the pounding of his own blood in his ears Enki heard a sickeningly loud snap.

 _That wasn't Enlil_ , Enki told himself. Enlil was fine. His brother fell heavily to the ground and lay still and Enki told himself that Enlil was just knocked out. Nothing more. Cas could heal him now he was back to full strength.

The _Asag_ raised its arm to crush Enlil again and Enki ran forward, shouting at the thing, cursing it, wishing he had more salt or holy water or _anything_. Enki narrowly avoided a swipe from another of its arms as he threw himself up against the side of its body, trying to drive his knife into the joint where an arm joined its bulk, reasoning the skin there would be softer, more flexible, and therefore vulnerable. The blade didn't break but it couldn't penetrate its hide either and Enki screamed as the arm rushed towards his brother's unmoving body.

He hated himself for looking away, for concentrating instead on the leather-like flesh of the joint, stabbing at it repeatedly. Useless. It was fucking _useless_.

The world, his own life, nothing meant anything if Enlil wasn't alive. After all the shit they'd been through, for them to die here was not something Enki had believed would ever actually happen. There'd always been hope. There'd always been the belief that everything would come out alright in the end.

He looked to the sky. The rain fell in his eyes, blurring his vision. Hanging uselessly at his side his arm burned, his knife gripped so tightly in his one working hand that Enki could feel every indentation in the handle, the texture of the cord bound around the hilt of the blade.

"Castiel, you asshole," he cried. "Cas! You get your ass down here right the fuck now!"

The monster- the murdering fuck- lifted its arm again and if there was a chance, if there was any chance at all that Enlil might have survived Enki had to stop it. He scrambled over to his brother and there was so much blood that Enki had to look away. He couldn't see Enlil like this. In that glimpse Enki had seen the way the back of Enlil's head had been crushed. He'd seen the unnatural angle of his neck. Enki pulled at his brother's body anyway, trying to get out of the monster's reach, because he wouldn't accept it. Enlil was too heavy, the creature was too fast, and at the last moment the only thing Enki could think to do was to shove his brother away with all his remaining strength. The next thing he knew there was agony ripping along his leg and up his back and he thought maybe he screamed and maybe he couldn't breathe. He tasted blood and rainwater.

When Enki next opened his eyes, not remembering ever closing them, he found himself almost face down, stone pressing uncomfortably against his cheek. Turning his head just slightly so he could see more than gravel and blood was agony and Enki wished he hadn't moved at all when he found himself staring into his brother's open, dead eyes. Enki blinked the rain away and couldn't stop looking. Dimly, he was aware that the monster was close and it was going to finish him, but he had no weapon and he had no strength. Every part of him was pain and cold and not much else. Enki wasn't sure he could even move. He was dying, he realised, and without Enlil he didn't really care.

Enki waited for the end. He didn't think about how he'd failed. He didn't think about what would happen to the world now, and he certainly didn't think about Cas. _Castiel_.

Listening now, trying to concentrate on something other than Enlil's eyes and the pain, he heard the crunching of stone. It was a strange sound when the last thing he remembered hearing was the creature's deafening roars.

He was waiting and waiting and the monster had never been this damn slow before and Enki found himself hating it. He wondered how intelligent the thing was; if it was drawing this out, taking pleasure in his slow death.

Then there were hands on him, gently turning him over. Human hands, gentle and familiar even though they'd hardly ever touched. Enki had never dared because he'd watched and he'd wondered and sometimes he'd thought about those hands and what he could teach them to do and every time Enki had known it was impossible.

Framed by a grey sky, Castiel's face looked pale, washed out and unclear. Or maybe that was just because Enki was finding it difficult to focus on anything anymore.

"Enki," he said, and there was sadness in his voice. But what right did Castiel have to be sad when he could've _stopped this_?

"You finally showed up." It was difficult to speak, Enki's throat somehow dry despite being pretty much drowning in water. "You're too fucking late."  
It was hard to feel hate. It was hard to conjure the energy for it, but Enki was really trying.

"Enlil is _dead_." Enki knew he was crying. Usually this would've bothered him but what the hell. He was going to die and Castiel was the same as all the other supernatural bastards he'd ever killed.

Castiel, whose eyes he knew and who always stared at him like there was nothing else in the world, looked away. "I'm sorry."

Enki snorted, felt his breath catch painfully in his chest. There was something wrong inside of him. Probably a lot of things wrong inside of him.  
"You don't even know how to be sorry," Enki accused, and Castiel didn't try to deny it.

"I told you," Castiel tried. "I told you this would be your death." Like that made it okay.

Enki was vaguely aware that Castiel was kneeling beside him, that he had Enki in his arms and pulled close up to his chest. Through the smooth fabric of Castiel's clothes Enki could feel his warmth. He watched as the red of his blood stained the material, red splintering outwards, spreading and mixing and making patterns across the white cloth.

"You could've stopped it. You could bring Enlil back, couldn't you?" It was weird how with all this pain Enki was still conscious. He was proud of how steady his voice sounded. Not like he was dying at all. "You sent the _Asag_ away."

"I didn't," Castiel said. "It was done with you. I can't bring Enlil back."

"No." Enki wanted to shake his head but it was too heavy. Cas's fingers were pressed against the back of his neck, Enki could feel them because there was no pain there. "You _won't_ bring Enlil back."

"It is not permitted." Still with his rules and his orders and nothing had changed. Enki closed his eyes. What the hell was the point of trying?

"So sticking with us really was just to get free," Enki sighed. He was exhausted and he wanted to sleep and he wanted the world to go away. He wanted Cas to fuck off and leave him to die in peace.

Those warm, gentle fingers stroked lines across Enki's cheeks. "It wasn't." Maybe Cas sounded like he meant it, but he wasn't even human, Enki reminded himself.

It was kind of a moot point now anyway.

"Why did you come here?" Enki asked. It seemed to Enki like maybe Cas was trying to soothe his own guilt. Like he was trying to make something right that he never could.

"Your death will be painful," he said, and Enki couldn't help laughing at that because it was just like Cas not to bother softening the truth at all. The laughter made him gasp for air, made his chest ache as though it was caving in on itself.

"Enki," he heard Cas saying. " _Enki_." He felt fingers brushing through his hair and lips against his lips breathing warm air into him. "I am forbidden from saving you," Cas said, and Enki heard the misery in his voice.

Enki would've liked to have said, _Don't do me any favours_. He would've liked to have told Cas to shove it, but whatever. It was over now anyway and Cas was close and warm and comfortable. There was one thing he wanted to ask.

Opening his eyes wasn't easy but for this he needed to see Cas. There was blood on Cas's lips and Enki would've sworn there was fear in his eyes. But maybe it was just wishful thinking, just Enki wanting to believe in these last moments that he'd gotten to Castiel after all. That the guardian spirit would mourn him. That his death would _hurt_ him.

"Why," Enki asked, and had to stop and breathe. It was so hard to breathe. "Why do you always stare at me?"

There was a long pause and Enki had almost resigned himself to Castiel not answering when he leaned over him, bent close to his ear as though he were afraid someone would hear. Cas whispered, "Because I know you." Enki didn't know what the hell he meant, other than it sounded vaguely stalkerish. He went on, "Because we will meet again."

That would be good, Enki thought. Then he'd be able to kick Cas's ass for not saving them.

He held Castiel's gaze for as long as he had the strength, and when he couldn't keep his eyes open any longer Enki could still feel Cas there, holding him, until Enki couldn't feel anything at all.

 ****

7.

They weren't being awkward, Dean told himself.

Cas was just tired and hurt and still kind of crazy, and that was why he hadn't spoken a word to Dean on the way back to find Sam. Cas hadn't made eye contact either, but that was because he was concentrating on the patterns on the walls, his eyes moving quickly over them as they passed. Dean had seen Sam do the same when he was reading complicated shit.

They found Sam and the civilians not far away, backed into a dead ended cave that was a lot less deep than Dean remembered it being the first time they'd passed it. It wouldn't offer much protection from the slug monster thing, and it definitely wouldn't hide them. It was creepy as hell, too, to be surrounded by the sigil-covered walls this up-close and personal. Dean didn't like to think what they were doing to Cas.

He meant to re-group, talk to Sam and try to come up with a plan. Let Cas rest a while. Even if Cas was more himself, more alert than he'd been in hours, he still looked like shit. They couldn't stop for long, because if they did Dean wasn't sure he'd ever be able to get moving again, but just a few minutes. A few minutes to take the weight off his busted ankle. A few minutes to close his eyes and try to forget how little sleep he'd had, how much his eyes ached, scratchy and raw and heavy. He would've done pretty much anything right then for some water, an ice-pack for his ankle, somewhere to _sleep_. From the way their two survivors leaned wearily against the walls Dean bet they would've too.

"Sam," Dean greeted his brother. He kept a tight hold on Cas, keeping him close and away from the walls, remembering what had happened to him the last time he'd touched the rock.

Glancing at Cas, Sam gave Dean a questioning look. Dean shook his head in response because now was really not the time to explain the method he'd used to get Cas to stop freaking out. There was a monster somewhere ahead of them and a crazy guy with a knife somewhere behind them and both had fallen silent. That was the most disconcerting thing of all. They were trapped, and Dean didn't have a clue which way they should go from here.

"You guys okay?" Sam asked, and Dean was relieved when he didn't press for anything more.

"Yeah." They weren't, not really, but they were still standing and that was something.

"I remember," Cas said. Then, in a move Dean wouldn't have thought Cas capable of considering the state he was in, Cas drew his sword from Dean's belt, shook off Dean's hold and split open a wrist before Dean could stop him.

"What the fuck-"

Dean tried to make a grab for Cas, to pull him back, because there was no way Cas could be back to being vaguely sane when he was busting open veins like that. But then Cas announced, "I can call down the creature responsible."

"Call that crazy dude here?" Sam sounded incredulous. "I thought we were trying to get _away_ from him?" Sam hesitated, torn between staying with the civilians and helping Dean deal with Cas. Cas who was busy finger painting even more sigils on the walls with his own blood, wincing every time he touched the stone.

"A human couldn't have done this alone. The knowledge doesn't exist on Earth," Cas said. "Only something powerful- and old- could have raised the _Asag_."

 _Asag_. Dean had heard Castiel mention that word a few times but there'd never been time to stop for an explanation. To ask how Cas knew what it was. Reaching out, Dean took a hold of Cas's arm and clamped his hand over the cut Cas had made across his own wrist, holding him back. It was ridiculously easy to hold him still. "You're going to kill yourself," Dean said. "Just stop for a second, would you?"

Scowling at Dean, Cas said dismissively, "There is no time to explain."

"Yeah," Dean scoffed. "You'd think by now you'd have learned that doesn't work on me. You tell me what the fuck is going on, Cas."

Dean didn't like the way Cas kept avoiding his eyes.

"I remember," Cas repeated, and he sounded so damn sad, like the words hurt, that Dean almost wished he hadn't asked. But he had to know so he could help. So he could keep them all alive.

"And?" Dean prompted.

"Six thousand years ago I- this creature caused a great flood."

Whatever Cas was remembering it didn't look good from the way he closed his eyes, his head bowed. Cas didn't seem inclined to offer anything more and Dean wondered what exactly had happened to put that look of loss and misery on Cas's face. Dean had never seen anything like it before.

It was the here and now and the staying in one piece that was important though. The rest they could deal with later.

Cautiously, knowing that these things never ended well, Dean asked, "How was it stopped?"

Cas still wouldn't meet his eyes. "It wasn't."

Yeah. Dean hadn't thought it would be that easy.

There was an uneasy silence as Dean tried to think of something he could ask that would make any sense of this. A billion years ago, or however long, the giant snake creature they were fighting had been released and done a shit load of damage and from the look on Cas's face he'd somehow been involved. Nothing had stopped it then, so what could stop it now? Sam must've been thinking the same thing because he asked, "Then what you're doing," he nodded towards the wall and Cas's blood, "If we bring it here, whatever it is that released that monster, then we can stop it?"

Beside Sam, the two remaining civilians stayed close, still blind and uncertain and Dean felt shitty for them because if he was in their situation- useless, defenceless and completely reliant on strangers- he'd hate it too.

"It is possible," Cas replied. It wasn't exactly the answer Dean had been looking for but it was better than running around clueless in the dark.

Irritably, Cas shook off Dean's hand, turning back to the wall. His fingers were stained red, spreading the shape of a line, another dissecting it, a half-circle. "Now let me finish," he ordered, and Dean was surprised by the anger in his voice. There was a lot more to this than Cas was saying but if this spell could get them out of here- or at least deliver the thing to them they needed to fight to get this hunt over with- then he could let whatever it was Cas wasn't telling them go. For now.

Cas paused suddenly and looked over his shoulder at Sam, considering. "I can bind the instigator here, so it cannot leave," he said. "But I will need to bind it to a person."

Sam pointed at himself, "To me?"

Cas held out a hand. "It would be preferable. I require your blood."

"Hey, now, hang on." Dean didn't like the sound of _binding_ and he sure as hell didn't like it in the same sentence as _to Sam_.

"Sam will be in no danger, Dean," Cas assured him. "I can't fight the _Asag_. I must seek an alternative, and this is the only one I can think of. We are out of time."

Looking pointedly towards the main tunnel, Dean knew that Cas was right. That didn't make it any easier to accept. And Sam, the little suck-up, was already offering his hand to Cas.

"Do it, Cas." Sam sent an exasperated look at Dean, and okay so maybe he was being overprotective but he'd not long gotten Sam back and maybe he was kind of paranoid about his brother getting caught up with any more spells or deals right now.

"You'd better be right," Dean murmured.

The truth of it was that he trusted Cas with this- Jesus- with Sam. Even if he was kind of crazy right now. Why the fuck else would Cas have kissed him?

"You can stand up at least now, right?" Dean asked. More magic could not be good, even if Cas wasn't looking anywhere near as unsteady as he had been. From what Dean could see the wound in his back had stopped bleeding, and Cas's eyes were much sharper, more aware.

"I can." Castiel gave Dean a long, searching look before he added, "I know this spell. Sam will be unharmed."

At Cas's assurance, Dean moved towards the edge of their cave, having to look away as Cas drew the point of his sword across the palm of Sam's hand. No matter how many times he'd seen it, Dean wouldn't willingly watch Sam get hurt. Instead, he leaned out into the tunnel cautiously, trying to work out where the monster and the knife-wielding maniac had gotten to. All he could see was a wide, empty passageway, and all he could hear was the occasional echo of falling rock, the shifting of the civilians, and Sam and Cas talking quietly behind him. In this maze of tunnels the sound reverberated, amplified, and Dean had to resist the urge to tell them to keep it quiet.

Just for a few minutes, Dean wished he could've sat down but he didn't dare even lean against the wall in case he fell asleep. He rubbed his hands over his face, blinking the sweat and the tiredness out of his eyes. He was unarmed again, he realised.

What felt like only a second later Cas called, "Dean," and at some point Dean had closed his eyes, propped himself against the arching rock. He must've fallen asleep after all, and he wondered how long he'd been out for. When he turned back to Cas and his brother, trying to look like he hadn't just passed out on the job, the expression on Cas's face was unlike anything Dean had seen before on the angel. It was like Cas didn't want to look away. Like he couldn't quite believe what he was looking at. It was hopeful, and there was- God- there was affection there, and Dean couldn't help but stare back.

"We must be ready," Cas said.

Dean nodded and moved to join them by the sigils Cas had drawn, hoping he survived this and hoping that when they got out of here Cas would maybe like to make out again sometime. Only without the craziness and the adrenalin and the exhaustion and the pain.

Once again Cas offered up his sword. "They will not be able to hurt Sam with this bond," he told Dean. He didn't need to mention that whoever or whatever they called down _would_ be able to hurt him. Dean could work out that much from the way Cas placed the sword in his hand, his fingers lingering and warm against Dean's palm. Since the first time he'd held it, back in the woods when they'd been looking for Sam, the sword had felt perfectly weighted in his hand. Now the sword felt even more _right_ , moulded around his fingers like a knife he'd been using for years. Dean ignored the implication, putting it down to crazy angel magic and nothing more.

"And you?" Dean asked, remembering the way he'd thought his fucking chest was going to explode when that asshole had sunk a knife into Cas's back. Cas had gone down and he hadn't gotten up again and it had been everything Dean could do not to freak the fuck out. Before that moment, Dean couldn't remember ever seeing Cas taken out by anything other than an archangel. And that crazy dude was no archangel.

"I will be fine." Cas looked confident as he turned away, back towards his sigils, but it was always hard to tell with Cas how much he was taking on blind faith. Standing beside Cas, watching him complete the circle that enclosed everything he'd drawn, Sam was frowning and nervous. He flexed his hand and Dean could see the blood on his palm. He didn't have time to tell Sam to bind it with something before Cas was speaking in a low voice, a string of short sounds. It wasn't the Enochian he'd been expecting, and it wasn't Latin. It sounded closer to whatever language Cas had been speaking in earlier, when he was half-crazed and confused. On the wall, Cas traced lines across the symbols he'd already painted. Right down in his toes, deep in his stomach, Dean felt the beginnings of powerful magic building around them and he gripped Cas's sword more tightly. Dean glanced around, not knowing where to expect this thing to appear. Close by, Sam was doing the same. His brother spared a glance to their two survivors. "Stay by the wall," he ordered. "Keep quiet and don't move, whatever happens."

They nodded numbly, both of them huddling against the wall. Dean saw the way their eyes were glassy with shock and confusion. There was nothing he could do about it, except protect them, and get them out of here alive. There had been so many he'd failed before, who'd been killed because he and his brother weren't fast enough or strong enough, and Dean was determined that these two wouldn't end up like that.

He made sure he was standing directly in front of the civilians before turning to Sam and calling, "Get over here."

Even if this thing couldn't hurt his brother, he was still unarmed and Dean had learned a hundred times over that it was better to be prepared, to be cautious, because anything could go wrong and usually did.

Sam shot him a mean sour face but did as he was told, moving to Dean's side and whispering, "I think I recognise that language."

"Language?" It hadn't occurred to Dean that Cas was doing something different, that this was something other than the usual abstract shapes that may or may not have been magical angelic script.

"Cuneiform," Sam said. "It's an ancient middle Eastern script."

"Human." Dean wondered just how many languages Cas could speak. "From about six thousand years ago?" he guessed, remembering that whatever Cas had forgotten had happened then. It never failed to feel seriously weird to think of Cas as that old. Half the time he acted like some clueless kid. There was so much he didn't know or understand and a lot of the time it had to do with humanity. How humans behaved. Emotions. It was the wrong time to be thinking about it, but Dean couldn't help wondering about how Cas had kissed him and if he even realised what it meant. Did angels even make out? Whatever was going on with them could all go so horribly wrong and Dean was almost glad he had Sam and a monster and a madman to distract him from having to deal with any of that right then.

"Yeah," Sam replied.

"Can you read it?" There was, Dean had found, no end to the amount of random crap Sam knew. But this time Sam shook his head regretfully.

They watched as Cas finished whatever he was writing, seemed to draw himself up to stand straight. He never stopped speaking and even though he never spoke any louder or sped up the words became heavier, somehow _more_.

Cas glanced back at them and Dean took it as a warning. He nodded to Cas to let him know he'd understood. In the next moment Cas slammed his palm down against the symbols like Dean had seen him do so often before, except this time he gritted his teeth and closed his eyes. Light erupted from the lines and curves, brightness filling the cave, spilling out into the tunnels and if the crazy dude and the monster hadn't known where they were before they certainly did now. All around them there was rumbling, like an earthquake, and somewhere in the distance Dean could hear stone cracking and splitting. Cas had never said anything about this damn spell causing a fucking cave-in. Wind rushed past his ears. It was the first air Dean had felt in too long and he didn't even have the chance to enjoy it. Over the noise, like thunder and gunshots but neither, Dean shouted to Cas, "Stop! You're gonna bring the roof down on us!"

There was every chance collapsing the tunnels would put an end to the monster and their crazy guy too, but Dean wasn't quite ready to take the self-sacrificing route yet.

He didn't know if Cas hadn't heard him, or if he was ignoring him, but he didn't stop, kept right on speaking with his hand pressed to the wall. The light around them intensified until it was blinding and Dean was forced to close his eyes, then cover his face with his arm when even that wasn't enough. Dean cursed and swore because he wasn't going to be much use protecting Sam and Cas if he couldn't even see. He yelled again, "Cas, stop!" Maybe Cas was caught up in his magic, or maybe he'd lost it again and just when Dean had damn well brought him back. As great as kissing Cas might be, necessity, to keep Cas sane, was not the way he wanted it to happen again.

The air filled with what sounded like the hissing, ear-splitting buzz of angel voices, growing steadily, piercing and painful. It was impossible to cover his eyes and his ears at the same time so Dean just had to grimace and bear it. It was more important, anyway, that he kept a careful hold of Cas's sword. Somehow, over everything, Dean could make out the civilians screaming. The air became choked with dust and the tang of electricity and Dean could taste it in his mouth; copper and power and ash.

Dean would've sworn he heard the familiar beating of angel wings but the screeching was so intense that his ears bled and it was impossible to be sure, or to concentrate, or to even remember which way was up and which way was down.

Suddenly, the sound was gone. The ground beneath Dean became solid again but his legs shook, his body fast enough in adjusting to the change. The air was still thick with dust and it made Dean cough and wheeze.

Somewhere in the distance the monster was howling and all Dean could think was that now they'd _really_ made it angry. After its long silence it was a relief to know that at least it wasn't anywhere close.

Then, Dean remembered what Cas had just been doing and what the whole light and sound show had been for and he realised, fuck, he couldn't see a thing. He couldn't see what they'd summoned. There were black spots blinding him, the air so full of crap his eyes watered every time he tried to open them.

"Sam? Cas, man, you okay?" he called, and hoped to hell that hadn't come out half as desperate and anxious as he thought it had.

No answer.

Damn it all but he should have known better than to let Cas do any magic shit in the state he was in.

He felt something bump into his shoulder, catching hold of him. "Dean."

It was Sam, voice rough and short of breath but there and strong and Dean felt himself relax slightly knowing his brother was safe. He would've asked Sam if he was okay, if he could see anything, if he could see Cas, but then another familiar voice cut through the coughing and the howling of the creature in the background and what the _fuck_.

"Well this is unexpected."

Balthazar.

There was no mistaking that smarmy bastard's voice anywhere. As the dust cleared Dean could see his scruffy face smirking right at them. He knew Balthazar was capable of a lot of shitty things, but he hadn't thought doing something that hurt Cas was one of them. They'd been too familiar with each other, Balthazar watching Cas too closely for Dean to believe it.

It made it even more unbelievable that Balthazar was out to do anything malicious when the next thing he did was to turn his attention to Cas with a concerned frown. "Cas. What happened to you?"

There were no demands to know what was going on, but instead a hand placed lightly on Cas's arm. "You're not healing," he said. "Cas. Heal yourself, you idiot."

He was an angel though, and despite his show of friendship Cas's spell had to have brought him to them for a reason and Dean did not trust him. Dean strode over to Cas's side, pulling him away from Balthazar's sticky fingers.

"Dean-" Cas frowned at him, annoyed, but Dean cut him off, "I don't wanna hear it. He started this crap. If your spell worked right," and Dean was not above playing on Cas's pride, "he was the one who messed with your head."

"I _what_?" Balthazar sounded incredulous and Dean turned to glare at him. Asshat. "Woah there, tiger. I think you're getting me confused with someone else."

"Cas's spell brought you here. You started this shit. Now tell us how to stop it."

"Stop what?" Balthazar took a step forward, stretching his arms out towards Cas and Dean raised Cas's sword in warning.

"I'd just love an excuse to use this. Please give me an excuse."

Balthazar looked at the knife in his hand, then to Cas, then back to the knife. There was surprise on his face. "Cassie-" he said in a low voice. "You gave him your _sword_." The grin that followed was sickeningly amused.

"Enough with the bullshit," Dean snapped. "You tell us what the fuck you did, and how we can undo it or so help me I will shove this-"

"Dean!" Cas gripped his forearm, pulling the blade away. "There's no need for this." He turned his attention to Balthazar. "Look around you, brother. I can't heal here. You can't leave. An _Asag_ has been raised again, and I was not the one to do it."

It was a weird thing to say, because of course Cas hadn't done it. Balthazar blinked, looked taken aback, and when he turned his attention to the walls of rock arching over them he actually flinched.

"These weren't-" Balthazar shook his head. "I didn't-"

The creature's howling started up again and Balthazar fell silent, listening. "Well, crap."

"Indeed." Cas was watching Balthazar closely, uncertain about something. "I remembered Eridu," he said.

At that Balthazar's eyes snapped to Cas's and for what felt like a long time the two angels stood staring at each other. He could hear Sam behind him checking on the civilians. The monster's screeching was getting louder and Dean just hoped Cas was interrogating the bastard or something because Dean was getting antsy, not liking how long they'd stayed in one place.

When Sam finally came over to join him, Dean leaned in close and whispered, "You know what Eridu is?"

Sam looked confused for a second. "Um. It was a city, I think. In ancient Mesopotamia."

Dean pointed to the symbols Cas had written on the wall, now burned black into the rock. "Same place that language comes from?"

"Yeah. Why?"

"Cas mentioned it."

"What're they doing?" Sam asked.

Dean shrugged because how they hell would he know? "Angel-talking?"

They watched Cas and Balthazar do a whole lot of nothing for a couple of minutes more until Dean couldn't stand it anymore. He unfolded his arms testily. "Enough with this shit."

He put a hand on Cas's shoulder, gratified when Cas's attention immediately turned to him. God but his eyes were _awesome_. There was that sadness again, old and somehow filled with guilt and when Cas looked at Dean now it was like he wanted to apologise for something.

"What's going on?" Dean demanded to know.

"Balthazar made me forget," he said. "Because I asked him to."

That was pretty much the last thing Dean had expected to hear.

"Okay," Dean said slowly. "Okay. Why would you do that? What did he do?"

Cas shook his head. "Balthazar did nothing."

"It was that psychopath of a human who is currently running around baying for blood. You teach them one little thing-" Balthazar laughed humourlessly. "Six thousand years and humans still haven't learned to keep well away from what they don't understand."

"And how exactly did he know how to raise this thing?" Dean demanded to know. "Cas said it was old knowledge."

"He taught this man," Cas supplied.

"Let me guess," Dean spat. "In exchange for his soul. And who cares that this thing is boiling everyone in Chicago to death?"

Balthazar folded his arms defensively. "He wanted power. I gave it to him. How was I supposed to know he was going to try for the apocalyptic devastation thing? He shouldn't even have been able to-"

"Yeah, well, he did and now here we are." It was too hot for this and it wasn't getting them any closer to escaping the tunnels or defeating the monster. "Tell us how to stop it."

"Stop it?" Balthazar scoffed. "You don't stop this creature. You _feed_ it."

Dean could guess exactly what the slug thing ate. "Humans."

"Souls," Cas clarified. "The _Asag_ doesn't kill directly, but brings disaster and through that feeds off the souls of those who die."

Cas sounded so tired and hopeless and it occurred to Dean that maybe he could guess what had happened six thousand years ago. Something Cas felt guilty about, something he hadn't stopped, something that had been so bad he'd asked Balthazar to make him forget.

Dean asked, "How many? How many have to die?"

Cas had said there'd been a flood.

"Thirty thousand. Thirty thousand souls and then the _Asag_ will be sated and sleep."

"You shouldn't have remembered." Balthazar shook his head regretfully. "I would never have let you remember."

Thirty thousand dead was a lot, too many, but over the course of human history Cas had to have seen hundreds of catastrophes. There had been a time not so long ago when Cas hadn't shown much regret over the death of humans, believing that they would find peace. Dean wanted to ask what had been different about six thousand years ago but Balthazar was glaring at him like he knew what he was thinking and Cas was enough of a mess without Dean pushing him about things he wanted to forget. So he let it go, saying instead, "Well, we don't have thirty thousand souls to spare. There has to be another way."

Silence.

The creature that Cas called an _Asag_ was hissing and growling and Dean was almost certain the damn thing was laughing at them. Ancient and invincible and Dean wondered how many humans it had killed.

Behind him the surviving woman was crying softly. Dean could think of nothing to say that could comfort her, his mind weirdly blank because he couldn't think of anything to suggest. All his years hunting and he had _nothing_.

Sam was looking at his feet, his brow furrowed in concentration but it didn't look like he had any more idea what to do next than Dean did. Across from them Balthazar had wrapped his arms around his chest looking more defiant than anything, denying that any of this was his fault. On any other day Dean might've considered punching the asshole just for that; Balthazar was the one who'd given some fucked up human knowledge he should never have had and he hadn't given a shit about the consequences. But with Cas mostly out of commission, Balthazar might actually come in useful. Dean wasn't blind to the fact that Balthazar seemed to do pretty much whatever Cas asked of him. Even now Balthazar was watching Cas closely, concern written on his face.

Cas was staring over his shoulder out into the wider tunnel behind them.

"There is another way," he said, his voice unusually quiet. He turned to meet Dean's gaze, regretful and resigned in a way that put Dean on edge, made him not want to ask what his other way was because it could not be anything that wasn't going to suck.

In the next instant Cas was gone.

"Cas!" he called, his stomach suddenly feeling hollowed out. "Cas! Get back here." When there was no reply Dean rounded on Balthazar. "Where did he go? Where the fuck did he go?"

Balthazar's eyes were wide with shock. He was shaking his head. "He wouldn't," he said. "He _wouldn't_."

"Wouldn't what?" Dean demanded. He raised Cas's sword and grabbed at the front of Balthazar's douchey t-shirt, hearing the fabric tear in his fist. Balthazar didn't resist even when he stuck the knife right up under his chin, just hard enough that the blade broke the skin. "You tell me what you've done. If you screw around I will end you." And he meant it. Dean didn't give a shit if he was Cas's friend. He would kill him for this.

Balthazar spared Dean a disdainful look, his body tensing and Dean knew what the bastard was about to do.

"Don't you fucking _dare_ -" Dean warned, tightening his grip on Balthazar's shirt as though that might somehow stop him, but before he'd even finished speaking there was the sound of beating wings and Balthazar was gone.

"Fuck," Dean swore. " _Fuck_."

The monster had fallen silent again and Dean's breathing was too loud in his ears. He turned to Sam.

"He's supposed to be bound to you, isn't he?"

Sam frowned at Dean. "I don't-"

A frantic sound cut Sam off, wings again only this time frantic and for a second Dean had the hope that it was Cas. It was difficult to reign in his anger when Balthazar appeared, doubled over and hissing, "You bastards. You've _cursed_ me."

Dean didn't point out that it was Cas who'd done the cursing. "You deserve it."

It was clear Balthazar was in pain from the way he stood upright cautiously, unsteadily, but the asshole still managed to glare viciously at Dean.

Balthazar looked Dean up and down like he was searching for something. "Not bound to you, I notice. _Your_ soul is already taken." Why was it, Dean wondered, that everyone was always bitching about his soul?

"My soul isn't taken by anyone," Dean snapped defensively.

Balthazar laughed unkindly, "You keep telling yourself that, Sunshine." His attention turned to Sam. "So I get you." Dean did not like the thoughtful grin spreading across Balthazar's face. "I think I can live with that." He took an unsteady step forward, reaching out to grab hold of Sam and oh, no. Dean was not letting Balthazar take Sam anywhere. He put himself between them, raising Cas's sword.

"You're not going anywhere."

"I can't get to our beloved Cassie to stop him doing something ridiculously stupid if you don't let me take Sam."

"No. You explain where Cas has gone. _How_ he's gone. I thought you guys couldn't fly down here." It wasn't betrayal, Dean told himself. There had to be a reason.

Balthazar's face twisted in irritation and impatience, but he backed up when Dean shoved the blade up under his neck again. He'd seen Cas fight enough times to know the throat was the weak point; the place that killed.

"We can fly short distances, and it isn't exactly pleasant, but I'm rather more concerned with saving my brother. The state Cas was in I doubt he could even carry one of you, let alone more, and being the caring guardian angel he is he stuck around."

"Then why did he leave now?" Sam questioned.

"Because Grace is worth a whole lot more than a human soul," Balthazar replied vehemently, looking between them like that should explain everything.

Then Dean understood and he felt his face go cold. "Worth thirty thousand souls?"

Beside him, Sam tensed. "Oh god. Shit."

"More than that," Balthazar replied. "I'm sure he thinks he'll survive."

Dean was going to find out, he determined, how to do that damn binding spell himself so he could make sure Cas never did this to him again. So he'd never have to feel this sick and afraid that everything he'd just gained was about to be lost forever.

***

"I should fucking kill you," Dean spat, and it was maybe the fiftieth time he'd said it but it was worth saying again.

"It's not _my_ fault Castiel has developed a rather disturbing suicidal streak." At Dean's sour look Balthazar amended, "Sorry, _self-sacrificing_ streak. If anyone's to be blame here, it's you two."

They'd long since taken to smaller, increasingly claustrophobic tunnels. They splintered and diverged into a haphazard maze that Dean was sure none of them would ever be able to find their own way out of. They were following Balthazar, _trusting_ Balthazar, and just for that Dean was going to rip Cas a new one when he got his hands on him.

They were moving as fast as they could, which wasn't very fast at all with Dean's ankle so swollen it was agony to put any weight on at all. He hobbled along, gritting his teeth and using the wall for support and wishing he could lean on Sam instead. It had quickly become obvious that Dean couldn't keep a lookout for anything that might attack them and walk at the same time so he'd reluctantly handed over Cas's sword to his brother. Not that he thought Cas would mind, but using Cas's sword felt kind of intimate in a way Dean wasn't going to think about. It didn't help that Dean was back to being weaponless.

Balthazar, for all his bleating, had so far proved himself to be entirely fucking useless. He was as powered down as Cas had been, unable to locate Cas and unable to offer any useful input to their plan for what they were going to do when they found Cas.

The only helpful thing he'd contributed was to put their two civilians to sleep, leaving them hidden in the recess. They were protected, Balthazar said, and he'd drawn sigils around them in his own blood to prove it. Dean still wasn't entirely convinced, but leaving them behind had to be safer than going where they were headed.

Dean was even more convinced it was the right decision to leave them behind when they realised they were being followed.

"How do you work that out?" Sam demanded, and Dean remembered he was supposed to be arguing with Balthazar. It was easier than thinking about what Cas was doing right now. That he was alone and had somehow gotten it into his stupid angel brain that serving himself up on a platter to the monster would solve everything.

Hadn't he had this conversation with Cas? The one where he'd told him that they were a team and they dealt with shit _together_? Except maybe he hadn't. It was true that Cas had been distant lately, wound up with his own business and now that Dean thought about it he realised that not once had be offered Castiel help. It was entirely possible they'd been talking at each other more than they'd been talking to each other and maybe Cas hadn't understood that all he had to do was _ask_. Cas didn't always get things that were only implied, and Dean's attitude to all things angel probably hadn't helped.

So he was a dick. Dean knew that. But he'd thought for sure Cas would know he wanted him to stick around. God, especially now, after-

"Let me think," Balthazar said, all mock-sincerity, "Oh, yes. He never got himself killed before he met you."

It was a fair point, but Cas had made his choices.

"And none of us would even be here if it wasn't for your messed up deals, " Dean argued. " What is with that? You're supposed to be an angel, not a freaking demon."

There was something deeply satisfying about the way Balthazar turned to Dean, anger in his eyes, knowing he'd gotten that reaction out of the smug bastard. "I've been fighting demons since before your species dragged itself out of the primeval ooze, boy," Balthazar hissed venomously. "Don't you dare call me one of _them_."

"If the shoe fits, man," Dean threw back.

There was a wrath in Balthazar's eyes that Dean had never seen before and if Dean was anyone other than himself he might've been afraid. But this was Balthazar, and he'd gotten them into this fucked up mess and it was his fucking fault Cas wasn't with them. With _him_. Just when he'd thought they were finally getting somewhere.

He snarled right back at Balthazar, daring him to do something about it and from the way Balthazar took a step towards him thought he actually might. Except then Sam stepped between them, putting his arms up and pushing them apart.

"Guys, guys." His eyes flicked to the tunnels behind them meaningfully. "This is not helping Cas."

Fuck but Dean hated it when Sam was right.

Balthazar scowled at Sam. "And you. I am not talking to you."

"Fine. Whatever. I'm sorry you're bound to me." Not that Sam sounded sorry at all. "Can we please go find Cas now?"

"I could find him more easily if your brother here would let me just take you with me. I could search faster than-"

"Not a chance," Dean cut in. "If we're gonna take this monster down then it's going to take all of us to do it."

"Take it down?" Balthazar snorted, incredulous. "How many times do I have to tell you, we _can't kill it_."

As many times as Dean had heard that, he still didn't believe it. All his life people had told him this was impossible, that was invincible, and not once had it proved true.

Dean was tempted to tell Balthazar this, along with a few choice other things, but Sam was right. They had to keep moving. They hadn't heard a sound from the monster since Cas had disappeared and Dean might've thought that Cas was already dead, the creature with him, except that Balthazar was certain they were both still in the tunnels.

"Can't you smell it?" Balthazar had asked, and yeah. Dean could. And Dean had never thought he'd be _glad_ to smell rotting, putrid fish.

They had some time, Balthazar assured them. Cas was hurt and wouldn't be able to move very fast. It wouldn't be easy for him to find the monster in these tunnels. Unless he got lucky. Unlucky. Whichever.

To make matters that much more fun it had become increasingly obvious that their resident psychopath human was stalking them. It was clear he knew the tunnels well, a shadow disappearing from behind them to reappear ahead of them, hidden down a narrow tunnel or further along their path. At least if he was following them, he wasn't going after Cas.

There was no point arguing with Balthazar anyway.

Dean wanted to sleep, and he wanted a cold beer, and he wanted to take Cas and Sam to this awesome diner he knew over in Logan Square. Maybe he'd convince Cas to try something. Maybe tease Sam about his serious deliberations over side salads. But what he got was endless tunnels that were hotter than fucking Hell- and Dean would know- and the constant feeling that he was going to get to Cas too late.

He picked up the pace, not caring how much it hurt his ankle or pulled at his muscles or how he didn't have the energy for it. When they came to another place where the paths split Balthazar told them, "This way," indicating the tunnel breaking off to their left. He made no further comment, and that was a first.

"It's guilt," Balthazar said suddenly three turns later, once going back on themselves and all the time Dean wondering if Balthazar actually had any clue where he was going. "He's doing this out of guilt. Not because of you."

"Guilt over what?" Sam asked. He looked tired and worn, his face red from the heat and the exertion, his footsteps heavy, but his voice was steady and clear.

For a second Dean was sure Balthazar was actually going to answer the question, but then out of _nowhere_ the crazy guy- the asshole who'd stabbed Cas and who'd somehow managed to release a massacring monster- sprung out at them. He made straight for Balthazar, burying his silver knife deep in the angel's shoulder. He laughed hysterically even as Balthazar growled and brushed the guy off with a sweep of his hand that looked like nothing more than a vague gesture but sent the man sprawling. Balthazar looked pained and angry as hell, the knife still embedded deep in his flesh. Close to his neck, Dean thought. Maybe this guy wasn't so crazy after all.

Before he could pick himself up Sam was on him, slamming his fist in the guy's face when he wouldn't cooperate and stay still.

Even unarmed he was dangerous, biting and kicking and scratching. He threw dust and stones in Sam's eyes, reached out for Sam's neck while he was trying to rub the crap out of his eyes and Dean was at Sam's side in an instant. He grabbed the guy's wrist, pinning it under his knees and slammed his head back with a palm to the chin. He watched, viciously satisfied, as the crazy guy relaxed under them. Not knocked out but dazed, his eyes rolling around unseeing in his head.

"You thought you could take us on?" Dean hissed. "You thought you could kill us too?"

It was difficult to stop himself beating the guy some more, but then Balthazar leaned over them saying, "All that magic he's been playing with has driven him insane." He smiled unkindly, grimacing in what looked like pain. At some point he'd pulled the knife out of his shoulder and the blood was thick and still spreading across his t-shirt. "I did warn him." There were a whole lot of things Dean wanted to say to Balthazar in response to that but he kept his mouth shut. Now wasn't the time to get into another argument.

"Stand him up," Balthazar ordered. "He can help us find Cas."

As much as Dean chafed at being told what to do by Balthazar, if it was going to get them to Cas he would do it.

"How?" Sam asked. His eyes were bloodshot and watering, and wiping the wetness away with the sleeve of his shirt didn't seem to be helping any.

"He can lead us to the _Asag_." Balthazar said it like it was the best fucking plan in the universe.

"I thought we didn't want Cas to get anywhere near that thing," Dean pointed out.

"What we want and what we have to work with are two very different things," Balthazar said haughtily. "Castiel will find the _Asag_. He's good at what he does and he's determined. Sooner or later he'll find it and then we'll be there to stop him."

"Unless we get eaten first," Sam added drily.

"Don't worry," Balthazar smirked. "It won't eat you, just your soul. You don't really need that anyway, do you, Sam?"

"You fucking asshole-" Dean wished he could do more than just glare at Balthazar but he wasn't stupid enough to loosen his grip on their psycho captive and the dick had to know that because he went on, "You were certainly doing fine without it before. Better, even-"

"Okay, stop," Sam interrupted. "I know we're all in pissy moods and it's too damn hot in here and we're all worried about Cas but bitching at each other is really not getting us anywhere. Do whatever you have to do, Balthazar. Dean. Help me with this."

Dean shot his brother a sour look, because he hadn't been _bitching_ at anyone.

Together they heaved the semi-conscious guy to standing. It was harder than it should've been in the oppressive humidity, and this guy was a lot heavier than he looked. This close up Dean could see that he was young. His clothes were filthy and stank of blood and sweat and rotting flesh. Every time Dean came across people like this, humans who'd given themselves over to evil magic, it always came back to power. To selfishness. To wanting something they were never supposed to have. For all the crap that he'd done in his lifetime, Dean sometimes thought he should've been able to sympathise but he couldn't, because he didn't deserve forgiveness any more than these assholes did.

"Get on with it, Balthazar," Dean demanded and was gratified when the bastard didn't argue.

Balthazar had one hand was clamped tightly around his shoulder, blood seeping through his fingers but he didn't seem so much concerned about it as irritated. He gave the silver knife in his hand a long look before handing it over to Dean.

"It's not as good as Cas's sword," he said, smiling creepily. "But like the George Michael song, you gave that away."

Dean ignored the comment, refusing to ask what exactly he meant by that, mostly because Sam was sniggering. Instead he snatched the knife out of Balthazar's outstretched hand. It felt good to be armed again even if it was with a weapon that had hurt Cas. It was even better than he had a weapon that could do damage to Balthazar.

Balthazar scowled at him like he knew exactly what Dean was thinking, and he probably did, but he turned his attention away to their captive.

"Right then. You're going to take us to the _Asag_."

The crazy guy blinked at Balthazar, uncomprehending.

"The giant slug monster thing," Dean supplied.

He snorted disdainfully "Why should I?"

"I gave you this power." Balthazar's voice was the most serious, the coldest Dean had ever heard it. "I can take it from you." The implied, _along with everything else_ , was obvious in Balthazar's narrowed eyes. As threats went it was kind of pointless because there was no way they were going to let this guy get away with everything he'd done; all the people he'd murdered, all the chaos he'd caused with his heat-wave producing monster. No one could be left with that kind of power and even Balthazar had to recognise that. If this guy had any sense at all he'd know it too.

"In any case," Balthazar added, "We'll just be devoured by your pet monster, won't we? What harm would it do to you?"

Looking between them, at the way the crazy dude peered at Balthazar suspiciously, it made Dean wonder if he actually knew what Balthazar was.

"Why would you-" The man looked horrified. "You're all fucking insane."

Yeah, Dean thought, because they were the ones running around slitting people's throats in their spare time. It worked in their favour though because anyone with any kind of logic would have wanted to know their motives, what they planned to achieve by going up against a soul-eating monster. Their guy just blinked some more before grinning widely and agreeing.

"He's gentle really," he laughed, and oh God, they were actually going through with this plan to follow the psycho.

Sam was, apparently, about as enthusiastic as Dean because he said, "Are we sure there isn't another way? Because this? It's a shitty plan, Balthazar."

"You forget, young Sam." Balthazar waved a hand dismissively. "I'm not talking to you. You should know, and I _know_ Cas knows, that binding spells are very difficult to remove. But he was a little confused, so I'll forgive him."

Cas had failed to mention that and Dean's gut twisted painfully, but it was something to worry about later. There was no way of telling when Balthazar was just bullshitting them anyway.

"Then talk to me," Dean insisted. "It could be a trap."

"A trap," Balthazar repeated derisively. "Of course it's a trap. A trap containing an enormous ancient world-destroying beast."

At least they knew what they were getting themselves in for.

Balthazar signalled for them to move and Dean was not gentle about nudging the crazy guy to start walking. Dean made sure to keep his wrist twisted behind his back. Sam had a hand gripping his shoulder tightly.

At every turn, every time the path split, their supposed guide took his sweet time deciding which route to take, humming thoughtfully and Dean knew the fucker was messing with them. He guided them into dead-ends and back again and laughed that he'd gotten confused and by the third time he did it Dean was ready to start throttling him. Then he mentioned Cas.

"Where'd the other one of you go?" he asked lightly. "The one with pretty eyes? I liked stabbing him. Did he die? Did I kill him?" He sounded so excited by the prospect that Dean lost it, spinning the bastard around and pressing the blade of his knife to the guy's chin.

"Dean!" he heard Sam yelling at him. "Calm down-"

"I will not calm down. I am going to cut this guy's eyes out-"

"No, you're not," Balthazar cut in and in the next instant the bastard was standing directly beside Dean, pulling his hand away, fingers wrapped around Dean's wrist tightly enough to bruise. "This gentleman is going to lead us where we want to go and he's going to do it directly so that you don't have to."

It was deeply satisfying to see the guy cringe away, swallowing thickly like he was afraid. He nodded emphatically.

After that, their progress was much more rapid. The path took them upwards and Dean felt the air lighten, becoming less old and stale. They had to be nearing the surface because sometimes Dean thought he caught a glimpse of sunlight. Unless that was just the dehydration and the exhaustion and he was starting to see things.

They barely spoke, listening for any sign of the monster, any hint of the outside world.

As they walked, to take his mind off the heat and the fatigue and the pain in his ankle, Dean turned over all the things he didn't understand about this case. Which was pretty much everything.

Mostly, Dean was trying to work out how the monster could've got Sam down into the tunnels and then retreated out of them again in what could only have been an hour at most when they had to have been trekking the fucking tunnels for at least that and had yet to find any way out. They'd been going slow and the guy had messed around with them, but surely a giant slug monster couldn't move _that_ fast.

And there were questions he had for Cas. He got that this creature- this _Asag_ \- was the same thing that had been released six thousand years ago when Cas had apparently been hanging out on Earth. Dean wasn't sure he wanted to know what the hell he'd been doing there. Not if it was something Cas didn't want to remember. But then, why did he remember now? Why did he keep looking at Dean and seeing someone else? A dozen times Dean thought to get the answers out of Balthazar, but every time they said more than two words to each other it turned into an argument and he never learned anything useful.

He understood that this sorry excuse for a human had released the creature, and from what Balthazar had managed to coax out of the guy it had all been kind of an accident. He'd taken the magic Balthazar had given him and he'd mixed it with other crap he'd found. It had been a blessing, he said. As soon as they were all dead he was going to go out into the world and Chicago was going to burn, and all of the souls would be _his_.

Worst of all, Dean got that Cas meant to get himself eaten by a monster to save them all.

"You got any ideas what we're going to do when we find it?" Sam asked and Dean shook his head.

"We'll think of something. We always do."

Balthazar gave them an incredulous look. "I often find myself wondering how you two can _possibly_ still be alive. Then I remember you have a guardian angel called Castiel."

"I don't see you coming up with any bright ideas," Dean shot back.

"You mean you don't intend to get eaten?" the crazy guy asked and he sounded genuinely surprised. Idiot.

Dean would've told him exactly how much of an idiot he was, but then the quiet was broken by a deafening howl. It was the first time he'd heard the monster's unmistakable screeching since Cas had disappeared and Dean felt his stomach go cold because Dean remembered this cry; it was the sound it had made when he'd stabbed the thing's eye. It was pain and anger and Dean _knew_ Cas had found the creature.

From the dark look on Balthazar's face, Dean guessed he'd come to the same conclusion. Their only consolation was that the creature sounded close. Dean rounded on their captive.

"Move," he ordered, leaning menacingly close. When the guy just stared back at Dean blankly he yelled, " _Move_ ," and shoved at his shoulder, urging him forward until they were half-walking and half-running. The pressure on his ankle was almost unbearable but he pushed on, snapping at their guide to go faster, to get them to the monster right the fuck _now_.

Another yowling sound and Dean held onto the fact that he'd only heard the monster's cries. Maybe Cas was winning. Maybe he was stronger than any of them had realised, or just stubborn enough to defeat this thing. If nothing else it was hope.

"He's not far," Balthazar announced. Glancing over, Dean could see that his eyes were unfocused, looking somewhere _else_ , and Dean envied him the ability to see that Cas really was still in one piece. He'd said that Cas wasn't far though, so Dean picked up the pace even more, ignoring the protests from their supposed guide. He didn't look nearly so smug now. There was fear in his eyes, panic when he stalled at every turn claiming, "I don't know. I don't _know_."

"If you don't know the way," Balthazar grinned, and it was a creepy, evil thing, "then I suppose we don't need you anymore."

He brandished his sword in the guy's face and, unsurprisingly, suddenly the guy knew _exactly_ which route to take.

They ran, the howls so loud the sound shook dust from the ceiling. Dean's lungs burned, not getting enough air, and all the time the tunnel narrowed around them.

"This can't be right," Dean yelled over the noise. It drove him mad that this guy could still be fucking with them now, when Cas was so close. If they got to Cas too late Dean was not going to be responsible for his actions. "There's no way that slug thing could get down here." The ceiling was so low Dean had to bend his neck. Sam was getting to the bent double stage.

"It'll lead us out-" the man insisted. He looked sickly and haggard, puffing heavily as they ran and Dean wondered who he'd been before magic and murder had twisted him. Dean knew better than anyone there was no going back from that.

There was a shrieking sound that set Dean's teeth on edge and made him think of nails against glass. Cas had to be winning. Cas would be fine. He could hold his own. He was a badass when he wanted to be, even without his sword, and he never gave up. He didn't back down, and it was something that Dean had always liked about Castiel. In that much, Castiel was a lot like him and his brother. Maybe too much like them.

Dean felt the movement of air and he could hear the scratching and scraping of rock against rock. They turned down another tunnels, down another, and then the crazy guy came to a halt. He pointed towards the end of the passageway.

"That way," he announced.

"Oh no, Sweetheart," Balthazar laughed and took the guy by the collar. "We're not leaving you behind."

He fought, trying to pull away and kicking out at Balthazar's legs as he was dragged along the tunnel, but there was no getting away from the angel's iron-strong hold. Balthazar seemed to take great pleasure in frightening the guy and Dean wondered if that had anything to do with the fact that his shoulder still bled, that Balthazar winced every time he moved his arm.

Beyond the end of the tunnel, Dean couldn't see anything but dust and stone.

"Can you tell if he's there?" Sam asked, obviously not convinced either.

Balthazar narrowed his eyes. "He is."

Suddenly less smug and confident, their captive tried to argue, "It'll kill you. You can't fight it. I can show you the way out."

"I didn't know you cared," Balthazar scoffed and the guy turned to Dean, his expression pleading.

"Don't look at me." Instead, Dean drew the silver knife and grinned. "I've killed things bigger than this." He wasn't sure that was exactly the truth, but whatever. Dean didn't miss the way the guy's eyes zeroed in on the knife like it was his own personal saviour, and Dean wondered what exactly the knife could do. He just hoped to hell it wasn't what had driven the man mad.

They had nearly come to the end of the tunnel now and Dean had no time to worry about it. He wasn't about to go up against a twenty foot long monster unarmed, cursed knife or not.

Closer now, Dean could see that the tunnel opened out into a larger cavern. He could hear scuffling, and then he could see the unmistakable black-brown tail of the monster flicking momentarily into view followed by a flash of tan. Cas's coat. It had to be Cas's coat.

The struggling creep in Balthazar's hold had slowed them down and as soon as they caught a glimpse of the creature he started screaming and freaking out. The monster had to have heard him over the sound of its own screeching because for an instant its cries cut off.

The next thing Dean knew there was an enormous yellow eye blocking the end of the tunnel, taking in each of them in turn. It wasn't like they'd been trying to creep up on the thing, but the element of surprise might've been useful. No chance of that now. Even if it hadn't done much good before, back in the woods, Dean couldn't resist the opportunity to take a swipe at the creature's eye with them so close and exposed. He launched himself forward, knife outstretched but only managed to scratch the surface of the soft skin before the creature reared back and for the first time Dean got a good look at its head, flat like a snake with a huge mouth that snapped opened. Inside, Dean saw lines and lines of long needle-like teeth.

"Shit," he swore, because that mouth was headed straight for him. He scrambled back deeper into the tunnel, certain the thing was way too big to get to him. It didn't seem to care, its giant head pounding against the tunnel opening hard enough that the ground under his feet shook, the rock above his head and all around him cracking loudly. Further down the tunnel he heard Balthazar shout, "It's trying to bury us alive!"

Dean watched as the monster drew back, pounded against the opening again and this time rock broke free and Dean had to throw himself against the wall to avoid it. He looked back to where Sam and Balthazar, still holding onto the crazy guy, had their backs pressed against the wall too, trying to scramble towards the entrance. They must've known there was no getting past the monster and its teeth, using its head like a battering ram, but the tunnel was getting towards unstable and going deeper would only end up with them trapped.

Just as Dean was actually contemplating trying to get the creature to back off with the knife, maybe trying to get to its side and to one of its eyes, light exploded from behind it. Dean had to cover his face with his arm, shielding himself from heat and dust and blinding brightness. It was the kind of light that could only have come from an angel, and it sure as hell wasn't Balthazar's doing.

When Dean was able to open his eyes again, blinking away the black spots clouding his vision, the monster was gone. Scrambling to the tunnel entrance, needing to see Cas for himself, Dean caught sight of the idiot angel using his _fists_ to fend the creature off and holy fuck that had to hurt. Dean remembered how hard the monster's skin was. Cas might be an angel but Dean knew how weakened he was.

Dean lost sight of Castiel as the monster curled its massive body towards him, its tail whipping out. No way could Dean stand there and do nothing when, for the first time in hours, he'd finally gotten confirmation that Cas was still breathing. For all that time, Dean hadn't let himself acknowledge the possibility that Cas was gone. He hadn't realised how deeply he'd buried it all. How much it would've hurt if Cas really had been dead.

He needed to get the creature away from Cas.

Clambering out of the tunnel and out into the larger cavern was more difficult than it should have been because there were fallen rocks blocking his path, the ground uneven and unstable and navigating it made Dean's ankle burn.

He did the only thing he could think of, yelling out, "Hey ugly! Over here!" His voice echoed around the cave and Dean inched closer making sure to wave the knife in the direct line of sight of one of those freaky eyes in the thing's body. Behind him he heard Sam shouting at him but he didn't dare look away from the monster, remembering exactly how fast it could move. "Cas, you fucking idiot!" Dean called. "Tell me you have a plan that doesn't involve anyone dying!"

Hearing him was even better than seeing him, except he sounded winded, his voice unsteady as he tried to tell Dean, "You can't help me."

Dean gritted his teeth, growling, "That's what I thought," under his breath just as the monster's body convulsed and it lashed out. Its tail hit the wall beside Dean, missing him by inches. The collision sent rocks and dust flying and Dean dove away, staying low and keeping his eyes open even though he could feel them watering from the debris. He made it all the way to the other side of the cavern and from there he could see Cas. There was blood all down his back, all over his hands and face and Dean wanted to hurt something.

Cas turned his head to look at Dean. There was anger there, but resignation and maybe relief too. Their attention lingered too long though, or else Cas just didn't care anymore, because then the monster whipped its body around again and this time the side of its head caught Cas right in the chest, slamming him into the wall. Dean heard Cas's cry of surprise and pain and for a moment his body became obscured by the creature's head grinding him into the wall.

If Cas had been human there was no doubt in Dean's mind that he'd be dead right about now.

"Fuck," Dean swore. He turned back to the tunnel where Balthazar was throwing their cowering captive to the floor and Sam was fighting his way around the fallen debris towards him. "Sam. I need you and Balthazar to get that fucking thing's attention away from Cas."

Putting Sam in front of the monster like that was about the last thing Dean wanted to do, but his brother had Castiel's blade and Dean knew he could take care of himself. It wasn't much consolation, but there was Balthazar too.

Sam nodded and pulled on Balthazar's sleeve. Dean left them to it, trying to get closer without getting himself ripped apart by the creature's long, very pointy-looking claws.

Out the corner of his eye he could see Sam moving in, Balthazar at his side. Then, there was a flash of that angelic light, but not blinding, more focused, and the creature swung its head away from Cas turning to face down Balthazar. He could hear the angel saying to Sam, "Well I hope you have a plan for what we do next."

But Dean couldn't look away, watching in horror as Castiel's body slid heavily down the wall; a dead weight. As he weaved his way around rocks, past the creature's grasping claws, ignoring the way the eyes on its body followed him, Dean couldn't help but think that this was his fault. He'd distracted Cas. He hadn't been able to look away.

When he finally reached him it was the most awesome thing ever to see Cas's chest still rising and falling and his eyes half-open. His ears and nose were bleeding and what Dean could see of Cas's pupils did not look good. Any other time Dean would never have even considered moving someone after they'd just been pounded into a wall but he had to get Cas somewhere safe. Safer, at least.

Hooking his arms under Cas's, Dean dragged him as quickly as he could manage, whispering, "Sorry, sorry," when Cas groaned and gasped.

"This is what you get," Dean ground out, "for running away," and even though he had to be in one hell of a lot of pain, Cas's glare was still a fierce thing, "to deal with shit on your own."

The best shelter Dean could find was a hollow made up of a groove in the ground and the cavern wall. It wasn't much but it hid them partially from sight, enough that Dean could crouch down and check Cas over.

There were no sigils here, where the wall had part-collapsed. Dean hoped that would help.

"You're a dick, Cas. Jesus, I hate you sometimes."

Cas just smiled back at Dean, and it was soft and affectionate and sappy and half out of it. "I hate you sometimes too."

Head wound, Dean was sure, and ran a hand along the back of Cas's skull. Cas winced and tried to roll his head away but Dean held him still. He could feel thick wetness against his fingers that could only have been blood. He had nothing to press against the wound except for his hands and no way he could take Cas out of here without leaving Sam behind.

Dean glanced over to where his brother and Balthazar were picking away at the monster, slashing at its eyes and Balthazar distracting it with light and his sword. They were both keeping far away from the thing's mouth. From what Dean could tell they were holding their ground, but gaining nothing.

"I told you." Cas's voice was regretful, too quiet. "You can't stop this. I can."

"Not a chance." Dean's attention snapped back to Castiel. "I'm never going to let you just give up your life. I don't care what you did six thousand years ago or why you think you have to do this. You don't."

For a second Cas looked surprised, but then he shook his head. "You don't know what I did."

"I don't _care_." And Dean didn't. Whatever it was, Cas had been so consumed by guilt he'd gotten Balthazar to make him forget. Maybe that was the easy way out, but it showed a level of remorse that Dean could understand. Some days he thought he'd give almost anything to forget Hell.

Cas shook his head again. "There is no other way."

"There's always another way." They could drive the creature deeper into the tunnels, bury it alive under rock and stone. Even if that would only hold it for a little while, it would buy them some time. Time to rest and think and heal. If there was one thing Cas needed it was time to heal, his eyes tight with pain and the worst of it was his hands, purple and swollen, deep cuts along the knuckles and they looked so twisted and broken it made Dean feel ill. He had to look away.

"This is more effective than knives," Cas told him, stretching his fingers out painfully slowly. Then, "We must go and assist them."

"You're not going anywhere," Dean scoffed. "You can barely stand."

"I will be fine," Castiel replied irritably and Dean knew from long, long experience there was no point trying to stop Cas when he was like this; stubborn and determined and annoying as hell.

"You stick close to me," Dean insisted instead. "I might need rescuing." He grinned at Cas, enjoying the way Cas scowled back at him.

Standing up was more difficult every time he did it and Dean had to use the wall for support. Cas was watching him.

"You're hurt."

"It's just a sprain." Which might have been true when he'd first messed his ankle up but it was hard to tell now. Nothing he could do about it though, so Dean levered himself upright, putting a little weight on his foot to show Cas it was nothing. Cas didn't look convinced.

One second Dean was looking down at Cas, the next something was barrelling into his side, knocking him to the ground. It was his own damn fault for letting his attention focus too completely on Cas, he berated himself. He hadn't noticed the guy approaching at all.

How the crazy bastard had gotten from one side of the cavern to the other without Sam or Balthazar noticing, or the monster flattening him, Dean didn't know. He guessed he couldn't blame them for not noticing him getting away, seeing as they were fighting a massive slug creature. However he'd done it, he was after something, grappling at Dean's clothes and repeating, "Give it back, give it back." He was doing a damn good impression of Gollum, Dean decided. It was creepy.

"Give me the knife," he snarled and actually bit into Dean's neck like a fucking vampire. It hurt like hell and Dean cried out, elbowing the guy in the stomach.

Suddenly the weight was gone from his back, and when Dean rolled over to see what the crazy guy was planning next, he saw Cas standing over him holding the man by the neck, his captive gasping for breath.

Dean got to his feet quickly, pulling the silver knife from his belt. "This knife, you mean?"

The guy hissed at him and made to reach out and grab it but Cas held him back, squeezing his fingers more tightly around his throat.

Since he'd last checked, the monster had moved closer and it howled now in anger. The man panicked, punched Cas in the face with enough force that he let go, staggering back. Dean was going to _hurt_ this guy for that. Seeing the look on Dean's face the man backed up, his hands held up placatingly. "You use the knife," he offered. "You can control the monster. Give it to me and I can show you how." His smile was sickeningly false.

"There is no way in hell," Dean told him, "I am giving you a weapon."

The guy snarled, backing up further like he was trying to get away from Dean.

Sam shouted, "Dean!" and when Dean looked up he saw the creature headed directly for them. Or more specifically, for the crazy guy.

" _Move_ ," Dean urged, gesturing for him to get behind them. But the man didn't move, rooted to the spot in terror. He turned to look behind him and before Dean could do anything the creature was on him, its huge mouth devouring him whole. Not even a scream, just a sharp crunching sound and he was gone.

"Shit," he heard Sam swear. "I thought you said it didn't _actually eat people_."

"Must've made an exception," came Balthazar's off-hand reply.

The monster looked up and Dean knew it had zeroed in on him, arching its whole body towards him, preparing to strike and it really was a whole lot like a giant snake. Except with creepy claw hands and too many eyes. Dean really didn't want to get eaten, so he backed up slowly, watching as the creature matched his every move. If it was going to swallow him whole then Dean was not going to go out without a fight. He lifted the silver knife, readying himself. It was weird, but Dean could've sworn the creature narrowed the eyes on its head at the sight of the knife and then he remembered; the crazy guy had said this could control the monster. It didn't _look_ very controlled.

Then, Cas was at his side, so close he was almost leaning against him.

"Get the fuck away-" Dean protested, but Cas cut in, "Repeat my words, Dean." Without any further explanation he began enunciating sounds, slowly pronouncing syllables, one after another, waiting for Dean to copy him. He did his best to get every intonation, every sound right, knowing the difference it could make to a spell. The blade in his hand became unnaturally hot but Dean held on, realising this must be how you controlled the thing. The instant he began reciting the phrases it was like the creature had been frozen, unable to move. Dean knew it was fighting the control, could feel it somewhere in the pit of his stomach, in his chest when he formed the words of the spell.

To Dean's relief it was a short incantation and when it was finished Castiel told him, "Hold its gaze. Say nothing more," then was gone. Dean would've loved nothing more than to tell Cas exactly what he thought of this plan but he didn't dare. Finally they had a weapon against the creature, even if all it did was hold it still. It was a chance.

As much as Dean wanted to call for Castiel to come back and _tell him what the fuck he planned to do_ he kept his mouth shut. He'd just have to trust that Sam wouldn't let Cas do anything stupid, because he sure as hell didn't trust Cas not to.

Dean barely dared blink, looking into the creature's yellow eyes and seeing hunger there, and a cold intelligence that Dean hadn't expected. It wanted to kill him. It wanted to devour him. If that crazed guy had been controlling this thing for weeks with this knife then Dean could understand why the creature went directly for him. It had wanted vengeance.

To his left Dean could hear Cas and Sam and Balthazar arguing, Balthazar saying, "It won't kill us," and Sam saying, "I can't believe you'd even suggest that."

More than anything Dean wanted to be over there arguing with them, wanted to know what they were planning, but instead he was stuck here in a staring match with a monster that was at least six thousand years old. Its claws scraped slowly along the ground, fighting whatever magic was holding it, and Dean felt his heart rate rise, his breathing quickening as though he were running. Held still like this Dean could see the jagged edges of its skin, reptilian but grey as stone. Several of its eyes were bleeding pus. It had lost a couple claws from one arm and there was black blood oozing from the open wounds. At least they knew it wasn't completely invulnerable.

The palm of his hand had started to burn and he could feel the strain on his arm, like there was something trying to push it down, making it ache. He couldn't hold this thing for much longer and from what Dean imagined to be a gleeful look in the creature's eyes Dean was sure the monster knew it too.

He gritted his teeth and held on, because no way was he going to let Cas and Sam down. No way was he going to let this thing get to them when he could stop it.

With every passing second it became harder, Dean more out of breath, his blood pounding through his ears so fast it was making him lightheaded. Dean wanted to call out to the others to tell them to _hurry the fuck up_. He wanted to look away and he wanted to sit down. He could feel his body shaking with the strain. Just as Dean thought he would break- that he was going to let them all down again because he wasn't strong enough to hold even a simple spell- Sam was there holding his shoulder. Dean took strength from his brother's presence, let him take some of his weight.

"They're going to stop it," he said and Sam did not sound happy about it. He must've felt Dean tense because he assured him, "They promised me they'd be okay."

And Dean wanted to believe it, he really did, but there were Cas and Balthazar, walking right up to the creature and Dean had a terrible feeling he knew what they were going to do. His fears were pretty much confirmed when Sam said, "We should close our eyes."

Closing his eyes was just about the last thing Dean wanted to do, but the angels were reaching out to touch the creature's body and there was light already spilling from their eyes. The only satisfaction Dean got from any of this was that he could see fear in the monster's eyes.

Hoping that Cas would hear him Dean thought as clearly as he could, _You'd better be alright_.

He held his eyes open for as long as he could, narrowing them against the brightness, feeling the air become charged and heavy, a kind of heat filling the cave different from the humidity and closeness he'd felt for the past however many hours. This was more like ice burning at his skin, like being pricked by a million needles all over. He kept his eyes on Cas, watching his mouth speak words Dean couldn't hear, until he couldn't bear it anymore.

As soon as his eyes closed he heard the creature roar, but it was a different sound from any he'd heard before; this was somewhere between sated and angry. Dean felt his arm fall to his side, felt himself fall to his knees, Sam was there beside him. They clung onto each other as the light built, the screech of angel-voice rising, pressing in on them from all sides.

It was impossible to tell how long it went on for but it felt like forever, the whole world nothing but noise and brightness burning through his eyelids and pressure that made his ears ache. Then, in an instant, it was gone and there was silence. Darkness.

Dean sat, remembering how to breathe, remembering what it felt like to have legs and arms and fingers, waiting for the world to stop spinning. Sam was still there, his arm tight on Dean's shoulder, moving and alive. Blinking, remembering how to open his eyes Dean found he could see, more or less. Sam was rubbing his face, looking around.

The walls were scorched black, no trace left of the sigils that had decorated them. And in front of them the creature was gone. Where it had been lay Cas and Balthazar and neither of them moved.

"Shit." Dean's voice sounded raw and too loud in the silent cavern, too loud in his own head, to his own buzzing ears. He couldn't look away from Cas.

"Come on," Sam urged and helped pull Dean unsteadily to his feet. "He's okay," Sam said. "He's okay," and Dean didn't know which one of them he was trying to convince.

It was relief, fucking _joy_ , when they'd finally managed to stumble over to Cas's side and his eyes were open and there was life in them, watching Dean and Sam approach. The bastard had the gall to look _smug_.

"You remember," Dean said, folding himself against Cas's side, "that I hate you."

"I do," Cas assured him. He spoke in little more than a whisper but it was real. Dean pulled Cas onto his lap, wiping blood from his cheek away, careful of the bruises and cuts marring his face.

"I don't hate you," Sam smiled and Cas actually laughed, not much more than a puff of air but his eyes were warm when he turned them to Sam.

"Thank you," Cas smiled.

"And I'm assuming," came Balthazar's annoyed voice, "that no one hates me either, considering what I just did for all of you."

He was sitting up, looking groggy and dishevelled but one hell of a lot better than Cas.

"Seeing as you started this-" Dean began, but Cas took hold of his wrist, lightly tugging at him. "Dean." It was a request and a reprimand and Dean subsided. "Fine. Whatever."

He glared at Balthazar, and Balthazar smiled sweetly back. "We can get out of here now? I would really like to get this binding spell dealt with, unless you want me constantly at your side for the _rest of eternity_."

Dean shivered at the thought but Cas, the traitor, was laughing at him.

"We have to retrieve the civilians we left behind first," Sam reminded them and crap but Dean had forgotten about them.

"Can't we just leave them?" Balthazar dismissed. "I put them to sleep. They'll be fine for a few decades."

" _No_." Sam stood, pointing at Balthazar. "We are going to retrieve them. You still have enough angel mojo for that?"

Balthazar looked offended. "Of course I do. A half-powered angel is still a glorious thing."

Half-powered, Dean thought, and looked down at Cas. Beat up and looking about five minutes away from falling asleep but still smiling.

"Then we're going," Sam announced, hauling Balthazar up to standing. "You," he said, turning to Dean, "are gonna get Cas outside. We'll meet there."

"Oh, hell no, Sam," Dean protested. "You are not going back in there on your own."

"He'll have me," Balthazar cut in.

"Like I said. You're not going in there alone."

Sam raised his eyebrows. "You're not leaving Cas here alone. I know that's not what you're suggesting."

Manipulative little asshole.

"You'll only slow us down, Dean." Sam looked pointedly at Dean's ankle, and that fucking hurt, no matter how true it was. He was beyond exhausted, and there was no way Sam wasn't feeling it too. It was fucking incredible, Dean thought, that after everything Sam still had the energy and determination to go back into those damn tunnels. Just the thought of it made Dean feel cold. For Sam, to keep his brother safe, he would've done it in a heartbeat.

"You come back quickly Sam." He held out the silver knife and Sam took it, handing back Cas's sword.

"Thanks for the loan," Sam said to Cas. "It's an awesome weapon." Cas nodded back.

"Come on then, my overly-tall friend." Balthazar took Sam's arm. "Let's get this over with."

Before Dean could threaten Balthazar to not mess with his brother they were both gone. He couldn't decide if it was a comfort or not knowing that Balthazar would be weakened by the sigils down there.

"Balthazar won't leave him. He'll do as Sam asks." Cas sounded sure. "He is a fearless soldier."

Fearless was not a word Dean would have associated with Balthazar. "How can you trust him?" Dean asked. "He's-"

"My brother," Cas reminded him. "I've known him a very long time, and I have done things worse than he ever has."

For a long moment Dean just looked at Ca, knowing that he had no argument to that. Cas had to be talking about whatever had happened six thousand years ago. Whatever it was that had really started all this, long before Dean had even born. He'd told Cas it didn't matter, whatever he'd done, and he stuck to that. He trusted Castiel and that would have to be enough. "Let's get out of here then," he said finally.

Getting Cas to standing was not an easy thing, especially when his own ankle kept threatening to give way, but they made it. They followed the path of the cave upwards, more hobbling than walking.

"I hope you know where we're headed." Dean sure as hell didn't.

"Following this tunnel will lead us out."

There wasn't much more Dean needed right then than to get out of the caves, to see daylight and feel wind against his face and smell something other than death and decay. It had to be long past dawn by now.

"You want to ask," Castiel said after they'd been walking in silence for some time. There were shadows spreading across the walls, the sigils gone, and the smell of fresh morning air. They were so close to being out. _Outside_. And Dean couldn't deny that he did.

He started with something simple. Something safe. "You and Balthazar gave half your Grace to feed that thing, right? Is it dead? Will you get your mojo back?"

"The _Asag_ will sleep until it is awoken again. I meant it when I said it couldn't be killed. The curse it wove around this city is broken." Cas paused, taking a deep breath. He could see Cas's eyes were clear, focused, the blood that had matted his hair almost gone. He was healing. Leaning this closely together with his arm swung around Castiel's back, Dean could feel that he was warm again, not the sickly ice-cold he'd been in tunnels. A human warmth. "As to our Grace,” Cas continued thoughtfully. Unconcerned. "I don't know. I'm still an angel, if that's what you're asking."

It was and it wasn't, but Dean let it go. They'd turned a sharp corner and now Dean could see light, actual sunlight. He could feel its warmth. Not the sweltering, unrelenting humidity of before but something natural and welcome. A cool breeze swept over them and Dean thought it promised rain.

"That's not what you want to know though," Castiel guessed. "I will tell you."

With Sam, and with Balthazar, they'd stopped something that could've killed thousands and thousands of people. They'd come out of it alive and still upright, if Sam and Balthazar made it back okay with survivors too. With every step towards the outside world Dean could feel Cas's strength return, leaning just a little less against Dean, his face less creased with pain.

"Tell me later," Dean said.

"Dean," Cas sighed. "You must hear this. There are things I regret-"

"We've all done shitty things." Raising Lucifer. Everything that happened in Hell. They were things Dean knew he could never make up for, that he'd live with for the rest of his life. It was now that mattered, though. It was doing what they could to avoid repeating the mistakes they'd made in the past.

"You haven't been responsible for destroying an entire civilisation," Cas persisted stubbornly. It sounded like it hurt to say. It definitely hurt to hear. "I would do anything to undo what happened. I had friends who I betrayed because-"

"Because you were following orders?" Dean guessed. He still remembered Castiel when they'd first met. He still remembered how absolute and certain he'd been. How cold and inhuman.

Cas nodded, looking down at his feet. He was ashamed, Dean thought.

It was a story Dean wanted to hear. He wanted to know who Cas had thought he was all those times he'd lost it. He wanted to know how it had ended, even knowing that there was no way it had ended well. But the tunnel ahead of them opened out to light and the open sky and now wasn't the time.

"You won't like-" Cas began, and Dean knew from the way he was trying to draw away from Dean, from the way he looked at Dean like he might never see him again that Cas expected Dean to hate him for whatever he'd done. Dean held onto his shoulder more tightly, not letting him move away.

"Cas," he interrupted, catching and holding Cas's gaze. They'd stopped no more than a few feet from the mouth of the tunnel, Dean's eyesight adjusting itself back to normal so that he could see colour properly again. There was sun on one side of his face, light reflecting off of the buckles of Cas's coat. "I probably won't like it," Dean told him honestly, "But that doesn't change the fact that I trust you as you are now. It won't change the fact that you've done more for me and Sam- hell, for _Earth_ -than pretty much anyone I've ever known." Dean smiled at Cas, wanting him to understand. "You made the right choice this time, didn't you?"

Cas had chosen humanity and he'd chosen Dean, and Dean wanted Cas to know he was damn glad for that. For once, Dean thought that maybe he'd actually managed to say the right thing because then Cas relaxed against him, no longer trying to pull away.

There was still grief in his eyes, and a sad sort of guilt that Cas had been carrying with him since Dean and Sam had found him staring out across Lake Michigan. It was weird to think, but the fact that even six thousand years ago Cas had felt remorse over his actions strong enough to want to forget made Dean wonder if maybe Cas hadn't changed so much after all. Maybe he'd always been this awesome.

Cas's voice was certain when he replied, "I did."

It was easier to explain this way, Dean decided, taking hold of Cas's arms and turning him so that they faced each other. Cas made no attempt to stop him when Dean pulled him in for a kiss, his eyes staring right back at Dean like they always did, only this time he looked relieved, like maybe Cas hadn't expected to be able to have this again. There was no hesitation and no doubt in the way Cas kissed back, and that was all that Dean needed to know.

 ****

.END.

**Author's Note:**

> Thank you for reading! I hope you enjoyed, and I welcome comments and concrit warmly.
> 
> For those who are interested, in hopefully in not too long I will be compliling some historical notes, maps, and other useful things I used extensively during the writing of the ancient parts on my LJ.


End file.
